636539064 has 64 divisors (see below), whose sum is σ = 1914412800. Its totient is φ = 172295424.

The previous prime is 636539051. The next prime is 636539107. The reversal of 636539064 is 460935636.

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 96517 + ... + 102900.

It is an arithmetic number, because the mean of its divisors is an integer number (29912700).

Almost surely, 2^636539064 is an apocalyptic number.

It is an amenable number.

636539064 is an abundant number, since it is smaller than the sum of its proper divisors (1277873736).

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

636539064 is a wasteful number, since it uses less digits than its factorization.

636539064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199452 (or 199448 counting only the distinct ones).

The product of its (nonzero) digits is 349920, while the sum is 42.

The square root of 636539064 is about 25229.7258011259. The cubic root of 636539064 is about 860.2176589873.

The spelling of 636539064 in words is "six hundred thirty-six million, five hundred thirty-nine thousand, sixty-four".