51491968 has 32 divisors (see below), whose sum is σ = 111910320. Its totient is φ = 23404800.

The previous prime is 51491939. The next prime is 51491977. The reversal of 51491968 is 86919415.

It is a tau number, because it is divible by the number of its divisors (32).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16878 + ... + 19693.

Almost surely, 2^51491968 is an apocalyptic number.

It is an amenable number.

51491968 is an abundant number, since it is smaller than the sum of its proper divisors (60418352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51491968 is a wasteful number, since it uses less digits than its factorization.

51491968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36596 (or 36584 counting only the distinct ones).

The product of its digits is 77760, while the sum is 43.

The square root of 51491968 is about 7175.7904094253. The cubic root of 51491968 is about 372.0316001984.

It can be divided in two parts, 5149 and 1968, that added together give a palindrome (7117).

The spelling of 51491968 in words is "fifty-one million, four hundred ninety-one thousand, nine hundred sixty-eight".