251605317132 has 72 divisors (see below), whose sum is σ = 701631141120. Its totient is φ = 75528794880.

The previous prime is 251605317127. The next prime is 251605317133. The reversal of 251605317132 is 231713506152.

251605317132 is a `hidden beast` number, since 2 + 5 + 1 + 605 + 3 + 17 + 1 + 32 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (251605317133) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6537132 + ... + 6575507.

It is an arithmetic number, because the mean of its divisors is an integer number (9744876960).

Almost surely, 2^251605317132 is an apocalyptic number.

It is an amenable number.

251605317132 is an abundant number, since it is smaller than the sum of its proper divisors (450025823988).

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

251605317132 is a wasteful number, since it uses less digits than its factorization.

251605317132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13112703 (or 13112698 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

The spelling of 251605317132 in words is "two hundred fifty-one billion, six hundred five million, three hundred seventeen thousand, one hundred thirty-two".