251393864 has 32 divisors (see below), whose sum is σ = 517752000. Its totient is φ = 113902272.

The previous prime is 251393827. The next prime is 251393869. The reversal of 251393864 is 468393152.

It is not an unprimeable number, because it can be changed into a prime (251393869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32459 + ... + 39450.

It is an arithmetic number, because the mean of its divisors is an integer number (16179750).

Almost surely, 2^251393864 is an apocalyptic number.

It is an amenable number.

251393864 is an abundant number, since it is smaller than the sum of its proper divisors (266358136).

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

251393864 is a wasteful number, since it uses less digits than its factorization.

251393864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71957 (or 71953 counting only the distinct ones).

The product of its digits is 155520, while the sum is 41.

The square root of 251393864 is about 15855.4048828783. The cubic root of 251393864 is about 631.1291281950.

The spelling of 251393864 in words is "two hundred fifty-one million, three hundred ninety-three thousand, eight hundred sixty-four".