Camilo Sesto, a Spanish singer and songwriter who rose to prominence in the 1970s as a romantic balladeer, then went on to sell more than 100 million records, died Sept. 8 at a hospital in Madrid. He was 72.

His manager, Eduardo Guervós, confirmed his death to the Spanish public broadcaster TVE, saying that Mr. Sesto had suffered two heart attacks. He had been treated for kidney problems in recent years.

Mr. Sesto released about an album a year through the 1970s and ’80s, recording hits including “Algo de Mí,” “Perdóname,” and “Melina.” His song “Amor Mío, ¿Qué Me Has Hecho?” topped the Billboard Latin charts in 1991.

In 1975 he starred in the Spanish version of Andrew Lloyd Webber’s musical “Jesus Christ Superstar.” Mr. Sesto financed the theatrical production and later produced the cast album, with Ángela Carrasco as Mary Magdalene and Teddy Bautista as Judas.

Spain’s caretaker prime minister, Pedro Sánchez, tweeted that “Spain and all of Latin America mourn the loss of Camilo Sesto. His melodies will always be part of our memory.”

He was born Camilo Blanes Cortés in the city of Alcoy, in southeastern Spain, and studied at art school before launching a music career. Mr. Sesto took his stage name partly out of superstition: Sesto is an alternate spelling of sexto, Spanish for sixth, and he noted that his given, middle and family names each have six letters, and that he was the sixth member of his family.

“And if you want to be numerical about it, the street number of my house is 3399,” he told the Miami Herald in 1993. “Add the numbers and you get 24 — 4 and 2 makes six. My son was born on the 24th. Again, 4 and 2 equals six. . . . Is it a coincidence or something more?”

Mr. Sesto never married and had his son, Camilo Blanes, through a relationship with Lourdes Ornelas. Complete information on survivors was not immediately available.

He was scheduled to release a new album Sept. 13 and begin a U.S. tour in October.

“I want people to believe in what I do, to identify with what I do,” Mr. Sesto told the Herald. “And for that you have to give them your heart and soul. It must be a total submission.”