251121868 has 12 divisors (see below), whose sum is σ = 441136080. Its totient is φ = 125082992.

The previous prime is 251121863. The next prime is 251121883. The reversal of 251121868 is 868121152.

It is not an unprimeable number, because it can be changed into a prime (251121863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118303 + ... + 120406.

It is an arithmetic number, because the mean of its divisors is an integer number (36761340).

Almost surely, 2^251121868 is an apocalyptic number.

It is an amenable number.

251121868 is a deficient number, since it is larger than the sum of its proper divisors (190014212).

251121868 is a wasteful number, since it uses less digits than its factorization.

251121868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 238976 (or 238974 counting only the distinct ones).

The product of its digits is 7680, while the sum is 34.

The square root of 251121868 is about 15846.8251709925. The cubic root of 251121868 is about 630.9014289932.

The spelling of 251121868 in words is "two hundred fifty-one million, one hundred twenty-one thousand, eight hundred sixty-eight".