166139628525 has 504 divisors, whose sum is σ = 375011622720. Its totient is φ = 72492226560.

The previous prime is 166139628521. The next prime is 166139628527. The reversal of 166139628525 is 525826931661.

166139628525 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 3 + 9 + 628 + 5 + 2 + 5 = 666.

It is not a de Polignac number, because 166139628525 - 2² = 166139628521 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166139628521) by changing a digit.

It is a polite number, since it can be written in 503 ways as a sum of consecutive naturals, for example, 994847992 + ... + 994848158.

It is an arithmetic number, because the mean of its divisors is an integer number (744070680).

Almost surely, 2^166139628525 is an apocalyptic number.

166139628525 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166139628525 is an abundant number, since it is smaller than the sum of its proper divisors (208871994195).

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

166139628525 is a wasteful number, since it uses less digits than its factorization.

166139628525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 224 counting only the distinct ones).

The product of its digits is 4665600, while the sum is 54.

The spelling of 166139628525 in words is "one hundred sixty-six billion, one hundred thirty-nine million, six hundred twenty-eight thousand, five hundred twenty-five".