251081342121 has 16 divisors (see below), whose sum is σ = 354642624000. Its totient is φ = 157463524608.

The previous prime is 251081342023. The next prime is 251081342147. The reversal of 251081342121 is 121243180152.

It is a happy number.

It is not a de Polignac number, because 251081342121 - 2¹⁰ = 251081341097 is a prime.

It is a super-2 number, since 2×251081342121² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (251081342021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1109721 + ... + 1316678.

It is an arithmetic number, because the mean of its divisors is an integer number (22165164000).

Almost surely, 2^251081342121 is an apocalyptic number.

It is an amenable number.

251081342121 is a deficient number, since it is larger than the sum of its proper divisors (103561281879).

251081342121 is a wasteful number, since it uses less digits than its factorization.

251081342121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2428448.

The product of its (nonzero) digits is 3840, while the sum is 30.

The spelling of 251081342121 in words is "two hundred fifty-one billion, eighty-one million, three hundred forty-two thousand, one hundred twenty-one".