12506721928 has 8 divisors (see below), whose sum is σ = 23450103630. Its totient is φ = 6253360960.

The previous prime is 12506721911. The next prime is 12506721943. The reversal of 12506721928 is 82912760521.

It can be written as a sum of positive squares in only one way, i.e., 10036433124 + 2470288804 = 100182^2 + 49702^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 781670113 + ... + 781670128.

Almost surely, 2^12506721928 is an apocalyptic number.

It is an amenable number.

12506721928 is a deficient number, since it is larger than the sum of its proper divisors (10943381702).

12506721928 is a wasteful number, since it uses less digits than its factorization.

12506721928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1563340247 (or 1563340243 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 43.

The spelling of 12506721928 in words is "twelve billion, five hundred six million, seven hundred twenty-one thousand, nine hundred twenty-eight".