636687 has 8 divisors (see below), whose sum is σ = 943280. Its totient is φ = 424440.

The previous prime is 636673. The next prime is 636697. The reversal of 636687 is 786636.

It is a happy number.

It is not a de Polignac number, because 636687 - 2¹² = 632591 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 636687.

It is not an unprimeable number, because it can be changed into a prime (636697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11764 + ... + 11817.

It is an arithmetic number, because the mean of its divisors is an integer number (117910).

2⁶³⁶⁶⁸⁷ is an apocalyptic number.

636687 is a deficient number, since it is larger than the sum of its proper divisors (306593).

636687 is a wasteful number, since it uses less digits than its factorization.

636687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23590 (or 23584 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 636687 is about 797.9266883618. The cubic root of 636687 is about 86.0284293967.

The spelling of 636687 in words is "six hundred thirty-six thousand, six hundred eighty-seven".