51537636 has 18 divisors (see below), whose sum is σ = 130275782. Its totient is φ = 17179200.

The previous prime is 51537631. The next prime is 51537643. The reversal of 51537636 is 63673515.

It is a happy number.

51537636 is a `hidden beast` number, since 5 + 15 + 3 + 7 + 636 = 666.

It can be written as a sum of positive squares in only one way, i.e., 27625536 + 23912100 = 5256^2 + 4890^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×51537636² = 5312255848936992, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 1431601 = 51537636 / (5 + 1 + 5 + 3 + 7 + 6 + 3 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 51537636.

It is not an unprimeable number, because it can be changed into a prime (51537631) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 715765 + ... + 715836.

Almost surely, 2^51537636 is an apocalyptic number.

It is an amenable number.

51537636 is an abundant number, since it is smaller than the sum of its proper divisors (78738146).

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

51537636 is a wasteful number, since it uses less digits than its factorization.

51537636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1431611 (or 1431606 counting only the distinct ones).

The product of its digits is 56700, while the sum is 36.

The square root of 51537636 is about 7178.9717926734. The cubic root of 51537636 is about 372.1415520963.

The spelling of 51537636 in words is "fifty-one million, five hundred thirty-seven thousand, six hundred thirty-six".