51397928 has 32 divisors (see below), whose sum is σ = 99225000. Its totient is φ = 24944640.

The previous prime is 51397903. The next prime is 51397933. The reversal of 51397928 is 82979315.

It can be written as a sum of positive squares in 4 ways, for example, as 39715204 + 11682724 = 6302^2 + 3418^2 .

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 114248 + ... + 114696.

Almost surely, 2^51397928 is an apocalyptic number.

It is an amenable number.

51397928 is a deficient number, since it is larger than the sum of its proper divisors (47827072).

51397928 is a wasteful number, since it uses less digits than its factorization.

51397928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 845 (or 841 counting only the distinct ones).

The product of its digits is 136080, while the sum is 44.

The square root of 51397928 is about 7169.2348266743. The cubic root of 51397928 is about 371.8049812198.

It can be divided in two parts, 51397 and 928, that added together give a palindrome (52325).

The spelling of 51397928 in words is "fifty-one million, three hundred ninety-seven thousand, nine hundred twenty-eight".