636479646 has 64 divisors (see below), whose sum is σ = 1444849920. Its totient is φ = 185149440.

The previous prime is 636479639. The next prime is 636479707. The reversal of 636479646 is 646974636.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 368541 + ... + 370263.

It is an arithmetic number, because the mean of its divisors is an integer number (22575780).

Almost surely, 2^636479646 is an apocalyptic number.

636479646 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 636479646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (722424960).

636479646 is an abundant number, since it is smaller than the sum of its proper divisors (808370274).

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

636479646 is a wasteful number, since it uses less digits than its factorization.

636479646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1961.

The product of its digits is 3919104, while the sum is 51.

The square root of 636479646 is about 25228.5482340939. The cubic root of 636479646 is about 860.1908923644.

The spelling of 636479646 in words is "six hundred thirty-six million, four hundred seventy-nine thousand, six hundred forty-six".