51791972 has 6 divisors (see below), whose sum is σ = 90635958. Its totient is φ = 25895984.

The previous prime is 51791969. The next prime is 51792001. The reversal of 51791972 is 27919715.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 41654116 + 10137856 = 6454^2 + 3184^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6473993 + ... + 6474000.

It is an arithmetic number, because the mean of its divisors is an integer number (15105993).

Almost surely, 2^51791972 is an apocalyptic number.

It is an amenable number.

51791972 is a deficient number, since it is larger than the sum of its proper divisors (38843986).

51791972 is a wasteful number, since it uses less digits than its factorization.

51791972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12947997 (or 12947995 counting only the distinct ones).

The product of its digits is 39690, while the sum is 41.

The square root of 51791972 is about 7196.6639493588. The cubic root of 51791972 is about 372.7527153184.

The spelling of 51791972 in words is "fifty-one million, seven hundred ninety-one thousand, nine hundred seventy-two".