251121522542 has 16 divisors (see below), whose sum is σ = 417059356032. Its totient is φ = 112442472120.

The previous prime is 251121522529. The next prime is 251121522583. The reversal of 251121522542 is 245225121152.

251121522542 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 251121522499 and 251121522508.

It is a congruent number.

It is an unprimeable number.

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, 85182218 + ... + 85185165.

It is an arithmetic number, because the mean of its divisors is an integer number (26066209752).

Almost surely, 2^251121522542 is an apocalyptic number.

251121522542 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

251121522542 is a deficient number, since it is larger than the sum of its proper divisors (165937833490).

251121522542 is a wasteful number, since it uses less digits than its factorization.

251121522542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170367463.

The product of its digits is 16000, while the sum is 32.

Adding to 251121522542 its reverse (245225121152), we get a palindrome (496346643694).

The spelling of 251121522542 in words is "two hundred fifty-one billion, one hundred twenty-one million, five hundred twenty-two thousand, five hundred forty-two".