251225355421555 has 16 divisors (see below), whose sum is σ = 301508978241024. Its totient is φ = 200954584407520.

The previous prime is 251225355421511. The next prime is 251225355421603. The reversal of 251225355421555 is 555124553522152.

It is not a de Polignac number, because 251225355421555 - 2⁷ = 251225355421427 is a prime.

It is a super-2 number, since 2×251225355421555² (a number of 30 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 15 ways as a sum of consecutive naturals, for example, 2989063542 + ... + 2989147588.

It is an arithmetic number, because the mean of its divisors is an integer number (18844311140064).

Almost surely, 2^{251225355421555} is an apocalyptic number.

251225355421555 is a deficient number, since it is larger than the sum of its proper divisors (50283622819469).

251225355421555 is a wasteful number, since it uses less digits than its factorization.

251225355421555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153386.

The product of its digits is 15000000, while the sum is 52.

The spelling of 251225355421555 in words is "two hundred fifty-one trillion, two hundred twenty-five billion, three hundred fifty-five million, four hundred twenty-one thousand, five hundred fifty-five".