15987945656 has 64 divisors (see below), whose sum is σ = 33548774400. Its totient is φ = 7107205248.

The previous prime is 15987945629. The next prime is 15987945689. The reversal of 15987945656 is 65654978951.

It is a super-2 number, since 2×15987945656² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 15987945592 and 15987945601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 142145 + ... + 228431.

It is an arithmetic number, because the mean of its divisors is an integer number (524199600).

Almost surely, 2^15987945656 is an apocalyptic number.

It is an amenable number.

15987945656 is an abundant number, since it is smaller than the sum of its proper divisors (17560828744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15987945656 is a wasteful number, since it uses less digits than its factorization.

15987945656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86388 (or 86384 counting only the distinct ones).

The product of its digits is 81648000, while the sum is 65.

The spelling of 15987945656 in words is "fifteen billion, nine hundred eighty-seven million, nine hundred forty-five thousand, six hundred fifty-six".