636668325 has 36 divisors (see below), whose sum is σ = 1142577540. Its totient is φ = 338891520.

The previous prime is 636668323. The next prime is 636668341. The reversal of 636668325 is 523866636.

It can be written as a sum of positive squares in 6 ways, for example, as 39012516 + 597655809 = 6246^2 + 24447^2 .

It is not a de Polignac number, because 636668325 - 2¹ = 636668323 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636668323) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 125539 + ... + 130511.

It is an arithmetic number, because the mean of its divisors is an integer number (31738265).

Almost surely, 2^636668325 is an apocalyptic number.

It is an amenable number.

636668325 is a deficient number, since it is larger than the sum of its proper divisors (505909215).

636668325 is a wasteful number, since it uses less digits than its factorization.

636668325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5558 (or 5550 counting only the distinct ones).

The product of its digits is 933120, while the sum is 45.

The square root of 636668325 is about 25232.2873517246. The cubic root of 636668325 is about 860.2758827348.

It can be divided in two parts, 6366 and 68325, that added together give a triangular number (74691 = T₃₈₆).

The spelling of 636668325 in words is "six hundred thirty-six million, six hundred sixty-eight thousand, three hundred twenty-five".