251426513240 has 32 divisors (see below), whose sum is σ = 646525320480. Its totient is φ = 86203375872.

The previous prime is 251426513123. The next prime is 251426513251. The reversal of 251426513240 is 42315624152.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 251426513240.

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, 448975637 + ... + 448976196.

It is an arithmetic number, because the mean of its divisors is an integer number (20203916265).

Almost surely, 2^251426513240 is an apocalyptic number.

251426513240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

251426513240 is an abundant number, since it is smaller than the sum of its proper divisors (395098807240).

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

251426513240 is a wasteful number, since it uses less digits than its factorization.

251426513240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 897951851 (or 897951847 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The spelling of 251426513240 in words is "two hundred fifty-one billion, four hundred twenty-six million, five hundred thirteen thousand, two hundred forty".