636479856 has 200 divisors, whose sum is σ = 1914450384. Its totient is φ = 204042240.

The previous prime is 636479843. The next prime is 636479861. The reversal of 636479856 is 658974636.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 6561600 + ... + 6561696.

Almost surely, 2^636479856 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 636479856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (957225192).

636479856 is an abundant number, since it is smaller than the sum of its proper divisors (1277970528).

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

636479856 is a wasteful number, since it uses less digits than its factorization.

636479856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 261 (or 246 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 54.

The square root of 636479856 is about 25228.5523960452. The cubic root of 636479856 is about 860.1909869681.

The spelling of 636479856 in words is "six hundred thirty-six million, four hundred seventy-nine thousand, eight hundred fifty-six".