15660401625 has 128 divisors (see below), whose sum is σ = 31874618880. Its totient is φ = 7523712000.

The previous prime is 15660401609. The next prime is 15660401629. The reversal of 15660401625 is 52610406651.

15660401625 is a `hidden beast` number, since 15 + 6 + 604 + 0 + 16 + 25 = 666.

It is not a de Polignac number, because 15660401625 - 2⁴ = 15660401609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15660401625.

It is not an unprimeable number, because it can be changed into a prime (15660401629) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4193259 + ... + 4196991.

It is an arithmetic number, because the mean of its divisors is an integer number (249020460).

Almost surely, 2^15660401625 is an apocalyptic number.

15660401625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

15660401625 is an abundant number, since it is smaller than the sum of its proper divisors (16214217255).

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

15660401625 is a wasteful number, since it uses less digits than its factorization.

15660401625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3881 (or 3865 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 15660401625 in words is "fifteen billion, six hundred sixty million, four hundred one thousand, six hundred twenty-five".