51978574 has 12 divisors (see below), whose sum is σ = 81434376. Its totient is φ = 24835932.

The previous prime is 51978559. The next prime is 51978617. The reversal of 51978574 is 47587915.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 48367 + ... + 49429.

It is an arithmetic number, because the mean of its divisors is an integer number (6786198).

Almost surely, 2^51978574 is an apocalyptic number.

51978574 is a deficient number, since it is larger than the sum of its proper divisors (29455802).

51978574 is an equidigital number, since it uses as much as digits as its factorization.

51978574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2151 (or 1088 counting only the distinct ones).

The product of its digits is 352800, while the sum is 46.

The square root of 51978574 is about 7209.6167720622. The cubic root of 51978574 is about 373.1998440340.

Multiplying 51978574 by its sum of digits (46), we get a square (2391014404 = 48898²).

51978574 divided by its sum of digits (46) gives a square (1129969 = 1063²).

The spelling of 51978574 in words is "fifty-one million, nine hundred seventy-eight thousand, five hundred seventy-four".