251534136660 has 96 divisors (see below), whose sum is σ = 707877273600. Its totient is φ = 66735344640.

The previous prime is 251534136647. The next prime is 251534136701. The reversal of 251534136660 is 66631435152.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12272301 + ... + 12292779.

It is an arithmetic number, because the mean of its divisors is an integer number (7373721600).

Almost surely, 2^251534136660 is an apocalyptic number.

251534136660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251534136660 is an abundant number, since it is smaller than the sum of its proper divisors (456343136940).

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

251534136660 is a wasteful number, since it uses less digits than its factorization.

251534136660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21521 (or 21519 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 42.

The spelling of 251534136660 in words is "two hundred fifty-one billion, five hundred thirty-four million, one hundred thirty-six thousand, six hundred sixty".