251278321313 has 8 divisors (see below), whose sum is σ = 257131106496. Its totient is φ = 245425950000.

The previous prime is 251278321289. The next prime is 251278321321. The reversal of 251278321313 is 313123872152.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 251278321313 - 2⁸ = 251278321057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (251278341313) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1364723 + ... + 1537863.

It is an arithmetic number, because the mean of its divisors is an integer number (32141388312).

Almost surely, 2^251278321313 is an apocalyptic number.

It is an amenable number.

251278321313 is a deficient number, since it is larger than the sum of its proper divisors (5852785183).

251278321313 is a wasteful number, since it uses less digits than its factorization.

251278321313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206935.

The product of its digits is 60480, while the sum is 38.

The spelling of 251278321313 in words is "two hundred fifty-one billion, two hundred seventy-eight million, three hundred twenty-one thousand, three hundred thirteen".