636347640 has 64 divisors (see below), whose sum is σ = 1912636800. Its totient is φ = 169373312.

The previous prime is 636347629. The next prime is 636347641. The reversal of 636347640 is 46743636.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636347641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62851 + ... + 72269.

It is an arithmetic number, because the mean of its divisors is an integer number (29884950).

Almost surely, 2^636347640 is an apocalyptic number.

636347640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

636347640 is an abundant number, since it is smaller than the sum of its proper divisors (1276289160).

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

636347640 is a wasteful number, since it uses less digits than its factorization.

636347640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9996 (or 9992 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 39.

The square root of 636347640 is about 25225.9318955713. The cubic root of 636347640 is about 860.1314203343.

The spelling of 636347640 in words is "six hundred thirty-six million, three hundred forty-seven thousand, six hundred forty".