251631120660 has 24 divisors (see below), whose sum is σ = 704567138016. Its totient is φ = 67101632160.

The previous prime is 251631120647. The next prime is 251631120677. The reversal of 251631120660 is 66021136152.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2096925946 + ... + 2096926065.

It is an arithmetic number, because the mean of its divisors is an integer number (29356964084).

Almost surely, 2^251631120660 is an apocalyptic number.

251631120660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251631120660 is an abundant number, since it is smaller than the sum of its proper divisors (452936017356).

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

251631120660 is a wasteful number, since it uses less digits than its factorization.

251631120660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4193852023 (or 4193852021 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The spelling of 251631120660 in words is "two hundred fifty-one billion, six hundred thirty-one million, one hundred twenty thousand, six hundred sixty".