251345502440 has 32 divisors (see below), whose sum is σ = 565597783080. Its totient is φ = 100525684992.

The previous prime is 251345502437. The next prime is 251345502487. The reversal of 251345502440 is 44205543152.

It can be written as a sum of positive squares in 4 ways, for example, as 248795454436 + 2550048004 = 498794^2 + 50498^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 251345502440.

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, 62387 + ... + 711746.

Almost surely, 2^251345502440 is an apocalyptic number.

251345502440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251345502440 is an abundant number, since it is smaller than the sum of its proper divisors (314252280640).

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

251345502440 is a wasteful number, since it uses less digits than its factorization.

251345502440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 782261 (or 782257 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 35.

The spelling of 251345502440 in words is "two hundred fifty-one billion, three hundred forty-five million, five hundred two thousand, four hundred forty".