636988 has 24 divisors (see below), whose sum is σ = 1257984. Its totient is φ = 279600.

The previous prime is 636983. The next prime is 636997. The reversal of 636988 is 889636.

636988 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 636988.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636983) by changing a digit.

636988 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1131 + ... + 1597.

It is an arithmetic number, because the mean of its divisors is an integer number (52416).

2⁶³⁶⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

636988 is a deficient number, since it is larger than the sum of its proper divisors (620996).

636988 is a wasteful number, since it uses less digits than its factorization.

636988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 513 (or 511 counting only the distinct ones).

The product of its digits is 62208, while the sum is 40.

The square root of 636988 is about 798.1152798938. The cubic root of 636988 is about 86.0419841877.

The spelling of 636988 in words is "six hundred thirty-six thousand, nine hundred eighty-eight".