636659964 has 108 divisors (see below), whose sum is σ = 1704138072. Its totient is φ = 200376000.

The previous prime is 636659887. The next prime is 636659971. The reversal of 636659964 is 469956636.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 636659964.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1923279 + ... + 1923609.

Almost surely, 2^636659964 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 636659964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (852069036).

636659964 is an abundant number, since it is smaller than the sum of its proper divisors (1067478108).

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

636659964 is a wasteful number, since it uses less digits than its factorization.

636659964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488 (or 460 counting only the distinct ones).

The product of its digits is 6298560, while the sum is 54.

The square root of 636659964 is about 25232.1216706008. The cubic root of 636659964 is about 860.2721168817.

The spelling of 636659964 in words is "six hundred thirty-six million, six hundred fifty-nine thousand, nine hundred sixty-four".