51639900 has 72 divisors (see below), whose sum is σ = 160916784. Its totient is φ = 12710400.

The previous prime is 51639883. The next prime is 51639911. The reversal of 51639900 is 993615.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2721 + ... + 10520.

Almost surely, 2^51639900 is an apocalyptic number.

51639900 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

51639900 is an abundant number, since it is smaller than the sum of its proper divisors (109276884).

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

51639900 is a wasteful number, since it uses less digits than its factorization.

51639900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13271 (or 13264 counting only the distinct ones).

The product of its (nonzero) digits is 7290, while the sum is 33.

The square root of 51639900 is about 7186.0907314061. The cubic root of 51639900 is about 372.3875311704.

The spelling of 51639900 in words is "fifty-one million, six hundred thirty-nine thousand, nine hundred".