636970081 has 4 divisors (see below), whose sum is σ = 694876464. Its totient is φ = 579063700.

The previous prime is 636970067. The next prime is 636970097. The reversal of 636970081 is 180079636.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 636970081 - 2⁹ = 636969569 is a prime.

It is a super-2 number, since 2×636970081² = 811461768178293122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (636970031) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28953175 + ... + 28953196.

It is an arithmetic number, because the mean of its divisors is an integer number (173719116).

Almost surely, 2^636970081 is an apocalyptic number.

It is an amenable number.

636970081 is a deficient number, since it is larger than the sum of its proper divisors (57906383).

636970081 is a wasteful number, since it uses less digits than its factorization.

636970081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57906382.

The product of its (nonzero) digits is 54432, while the sum is 40.

The square root of 636970081 is about 25238.2662043176. The cubic root of 636970081 is about 860.4117736937.

The spelling of 636970081 in words is "six hundred thirty-six million, nine hundred seventy thousand, eighty-one".