251642263 has 8 divisors (see below), whose sum is σ = 256377440. Its totient is φ = 246926880.

The previous prime is 251642243. The next prime is 251642273. The reversal of 251642263 is 362246152.

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 251642263 - 2⁵ = 251642231 is a prime.

It is a super-2 number, since 2×251642263² = 126647657055522338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251642233) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22081 + ... + 31477.

It is an arithmetic number, because the mean of its divisors is an integer number (32047180).

Almost surely, 2^251642263 is an apocalyptic number.

251642263 is a deficient number, since it is larger than the sum of its proper divisors (4735177).

251642263 is an equidigital number, since it uses as much as digits as its factorization.

251642263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9897.

The product of its digits is 17280, while the sum is 31.

The square root of 251642263 is about 15863.2362082899. The cubic root of 251642263 is about 631.3369299228.

The spelling of 251642263 in words is "two hundred fifty-one million, six hundred forty-two thousand, two hundred sixty-three".