636639696 has 160 divisors (see below), whose sum is σ = 2278425600. Its totient is φ = 165352320.

The previous prime is 636639691. The next prime is 636639739. The reversal of 636639696 is 696936636.

636639696 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636639691) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23695 + ... + 42833.

It is an arithmetic number, because the mean of its divisors is an integer number (14240160).

Almost surely, 2^636639696 is an apocalyptic number.

636639696 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 636639696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1139212800).

636639696 is an abundant number, since it is smaller than the sum of its proper divisors (1641785904).

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

636639696 is a wasteful number, since it uses less digits than its factorization.

636639696 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19174 (or 19162 counting only the distinct ones).

The product of its digits is 5668704, while the sum is 54.

The square root of 636639696 is about 25231.7200364937. The cubic root of 636639696 is about 860.2629878954.

The spelling of 636639696 in words is "six hundred thirty-six million, six hundred thirty-nine thousand, six hundred ninety-six".