251132440 has 32 divisors (see below), whose sum is σ = 608514480. Its totient is φ = 92725632.

The previous prime is 251132417. The next prime is 251132459. The reversal of 251132440 is 44231152.

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, 240954 + ... + 241993.

Almost surely, 2^251132440 is an apocalyptic number.

251132440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251132440 is an abundant number, since it is smaller than the sum of its proper divisors (357382040).

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

251132440 is a wasteful number, since it uses less digits than its factorization.

251132440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482971 (or 482967 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 251132440 is about 15847.1587358744. The cubic root of 251132440 is about 630.9102823259.

Adding to 251132440 its reverse (44231152), we get a palindrome (295363592).

The spelling of 251132440 in words is "two hundred fifty-one million, one hundred thirty-two thousand, four hundred forty".