636744020 has 48 divisors (see below), whose sum is σ = 1460688768. Its totient is φ = 231231360.

The previous prime is 636744007. The next prime is 636744023. The reversal of 636744020 is 20447636.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636744023) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 217889 + ... + 220791.

It is an arithmetic number, because the mean of its divisors is an integer number (30431016).

Almost surely, 2^636744020 is an apocalyptic number.

It is an amenable number.

636744020 is an abundant number, since it is smaller than the sum of its proper divisors (823944748).

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

636744020 is a wasteful number, since it uses less digits than its factorization.

636744020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3920 (or 3918 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 32.

The square root of 636744020 is about 25233.7872702454. The cubic root of 636744020 is about 860.3099747938.

The spelling of 636744020 in words is "six hundred thirty-six million, seven hundred forty-four thousand, twenty".