51555636 has 48 divisors (see below), whose sum is σ = 145817280. Its totient is φ = 15622560.

The previous prime is 51555613. The next prime is 51555641. The reversal of 51555636 is 63655515.

51555636 is a `hidden beast` number, since 5 + 15 + 5 + 5 + 636 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 51555636.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20511 + ... + 22886.

It is an arithmetic number, because the mean of its divisors is an integer number (3037860).

Almost surely, 2^51555636 is an apocalyptic number.

It is an amenable number.

51555636 is an abundant number, since it is smaller than the sum of its proper divisors (94261644).

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

51555636 is a wasteful number, since it uses less digits than its factorization.

51555636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43421 (or 43413 counting only the distinct ones).

The product of its digits is 67500, while the sum is 36.

The square root of 51555636 is about 7180.2253446532. The cubic root of 51555636 is about 372.1848716893.

The spelling of 51555636 in words is "fifty-one million, five hundred fifty-five thousand, six hundred thirty-six".