636901216 has 72 divisors (see below), whose sum is σ = 1494344376. Its totient is φ = 266273280.

The previous prime is 636901207. The next prime is 636901217. The reversal of 636901216 is 612109636.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636901217) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 59335 + ... + 69241.

It is an arithmetic number, because the mean of its divisors is an integer number (20754783).

Almost surely, 2^636901216 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 636901216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747172188).

636901216 is an abundant number, since it is smaller than the sum of its proper divisors (857443160).

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

636901216 is a wasteful number, since it uses less digits than its factorization.

636901216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9972 (or 9957 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 636901216 is about 25236.9018700791. The cubic root of 636901216 is about 860.3807652293.

The spelling of 636901216 in words is "six hundred thirty-six million, nine hundred one thousand, two hundred sixteen".