251231001155 has 32 divisors (see below), whose sum is σ = 309062780928. Its totient is φ = 195993616000.

The previous prime is 251231001083. The next prime is 251231001163. The reversal of 251231001155 is 551100132152.

It is not a de Polignac number, because 251231001155 - 2²⁸ = 250962565699 is a prime.

It is a super-2 number, since 2×251231001155² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42556934 + ... + 42562836.

It is an arithmetic number, because the mean of its divisors is an integer number (9658211904).

Almost surely, 2^251231001155 is an apocalyptic number.

251231001155 is a deficient number, since it is larger than the sum of its proper divisors (57831779773).

251231001155 is a wasteful number, since it uses less digits than its factorization.

251231001155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7267.

The product of its (nonzero) digits is 1500, while the sum is 26.

The spelling of 251231001155 in words is "two hundred fifty-one billion, two hundred thirty-one million, one thousand, one hundred fifty-five".