51564444 has 12 divisors (see below), whose sum is σ = 120317064. Its totient is φ = 17188144.

The previous prime is 51564437. The next prime is 51564449. The reversal of 51564444 is 44446515.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51564449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2148507 + ... + 2148530.

It is an arithmetic number, because the mean of its divisors is an integer number (10026422).

Almost surely, 2^51564444 is an apocalyptic number.

It is an amenable number.

51564444 is an abundant number, since it is smaller than the sum of its proper divisors (68752620).

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

51564444 is a wasteful number, since it uses less digits than its factorization.

51564444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4297044 (or 4297042 counting only the distinct ones).

The product of its digits is 38400, while the sum is 33.

The square root of 51564444 is about 7180.8386696820. The cubic root of 51564444 is about 372.2060657360.

The spelling of 51564444 in words is "fifty-one million, five hundred sixty-four thousand, four hundred forty-four".