636129070929 has 27 divisors (see below), whose sum is σ = 1010020819899. Its totient is φ = 385516818720.

The previous prime is 636129070883. The next prime is 636129070979. The reversal of 636129070929 is 929070921636.

The square root of 636129070929 is 797577.

It is a perfect power (a square), and thus also a powerful number.

636129070929 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 621059053329 + 15070017600 = 788073^2 + 122760^2 .

It is not a de Polignac number, because 636129070929 - 2⁹ = 636129070417 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (636129070979) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 26307957 + ... + 26332125.

Almost surely, 2^636129070929 is an apocalyptic number.

636129070929 is the 797577-th square number.

636129070929 is the 398789-th centered octagonal number.

It is an amenable number.

636129070929 is a deficient number, since it is larger than the sum of its proper divisors (373891748970).

636129070929 is an frugal number, since it uses more digits than its factorization.

636129070929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48366 (or 24183 counting only the distinct ones).

The product of its (nonzero) digits is 2204496, while the sum is 54.

The spelling of 636129070929 in words is "six hundred thirty-six billion, one hundred twenty-nine million, seventy thousand, nine hundred twenty-nine".