251945155 has 32 divisors (see below), whose sum is σ = 377975808. Its totient is φ = 156624000.

The previous prime is 251945147. The next prime is 251945159. The reversal of 251945155 is 551549152.

It is a happy number.

It is not a de Polignac number, because 251945155 - 2³ = 251945147 is a prime.

It is a super-2 number, since 2×251945155² = 126952722255948050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (251945159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 193005 + ... + 194305.

It is an arithmetic number, because the mean of its divisors is an integer number (11811744).

Almost surely, 2^251945155 is an apocalyptic number.

251945155 is a deficient number, since it is larger than the sum of its proper divisors (126030653).

251945155 is a wasteful number, since it uses less digits than its factorization.

251945155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1827.

The product of its digits is 45000, while the sum is 37.

The square root of 251945155 is about 15872.7803172601. The cubic root of 251945155 is about 631.5901335915.

It can be divided in two parts, 2519 and 45155, that added together give a palindrome (47674).

The spelling of 251945155 in words is "two hundred fifty-one million, nine hundred forty-five thousand, one hundred fifty-five".