251040263 has 4 divisors (see below), whose sum is σ = 259138368. Its totient is φ = 242942160.

The previous prime is 251040233. The next prime is 251040271. The reversal of 251040263 is 362040152.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 251040263 - 2²⁴ = 234263047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251040233) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4049006 + ... + 4049067.

It is an arithmetic number, because the mean of its divisors is an integer number (64784592).

Almost surely, 2^251040263 is an apocalyptic number.

251040263 is a deficient number, since it is larger than the sum of its proper divisors (8098105).

251040263 is an equidigital number, since it uses as much as digits as its factorization.

251040263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8098104.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 251040263 is about 15844.2501558136. The cubic root of 251040263 is about 630.8330819799.

The spelling of 251040263 in words is "two hundred fifty-one million, forty thousand, two hundred sixty-three".