636012081 has 10 divisors (see below), whose sum is σ = 950092242. Its totient is φ = 424008000.

The previous prime is 636012073. The next prime is 636012119. The reversal of 636012081 is 180210636.

636012081 is a `hidden beast` number, since 636 + 0 + 1 + 20 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 635493681 + 518400 = 25209^2 + 720^2 .

It is not a de Polignac number, because 636012081 - 2³ = 636012073 is a prime.

It is a super-2 number, since 2×636012081² = 809022734355901122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (636012001) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3925920 + ... + 3926081.

Almost surely, 2^636012081 is an apocalyptic number.

It is an amenable number.

636012081 is a deficient number, since it is larger than the sum of its proper divisors (314080161).

636012081 is an equidigital number, since it uses as much as digits as its factorization.

636012081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7852013 (or 7852004 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 636012081 is about 25219.2799461047. The cubic root of 636012081 is about 859.9802055116.

The spelling of 636012081 in words is "six hundred thirty-six million, twelve thousand, eighty-one".