251278321290 has 16 divisors (see below), whose sum is σ = 603067971168. Its totient is φ = 67007552336.

The previous prime is 251278321289. The next prime is 251278321321. The reversal of 251278321290 is 92123872152.

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, 4187971992 + ... + 4187972051.

It is an arithmetic number, because the mean of its divisors is an integer number (37691748198).

Almost surely, 2^251278321290 is an apocalyptic number.

251278321290 is an abundant number, since it is smaller than the sum of its proper divisors (351789649878).

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

251278321290 is a wasteful number, since it uses less digits than its factorization.

251278321290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8375944053.

The product of its (nonzero) digits is 120960, while the sum is 42.

The spelling of 251278321290 in words is "two hundred fifty-one billion, two hundred seventy-eight million, three hundred twenty-one thousand, two hundred ninety".