51990804 has 36 divisors (see below), whose sum is σ = 131695200. Its totient is φ = 17294160.

The previous prime is 51990797. The next prime is 51990847. The reversal of 51990804 is 40809915.

It is a tau number, because it is divible by the number of its divisors (36).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20359 + ... + 22769.

It is an arithmetic number, because the mean of its divisors is an integer number (3658200).

Almost surely, 2^51990804 is an apocalyptic number.

It is an amenable number.

51990804 is an abundant number, since it is smaller than the sum of its proper divisors (79704396).

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

51990804 is a wasteful number, since it uses less digits than its factorization.

51990804 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3020 (or 3015 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 51990804 is about 7210.4648948594. The cubic root of 51990804 is about 373.2291117098.

The spelling of 51990804 in words is "fifty-one million, nine hundred ninety thousand, eight hundred four".