251351740561240 has 64 divisors (see below), whose sum is σ = 617273443683360. Its totient is φ = 91353348280320.

The previous prime is 251351740561223. The next prime is 251351740561303. The reversal of 251351740561240 is 42165047153152.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 146913049 + ... + 148614088.

Almost surely, 2^{251351740561240} is an apocalyptic number.

251351740561240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251351740561240 is an abundant number, since it is smaller than the sum of its proper divisors (365921703122120).

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

251351740561240 is a wasteful number, since it uses less digits than its factorization.

251351740561240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295529092 (or 295529088 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 46.

The spelling of 251351740561240 in words is "two hundred fifty-one trillion, three hundred fifty-one billion, seven hundred forty million, five hundred sixty-one thousand, two hundred forty".