636945716736 has 960 divisors, whose sum is σ = 2270122702848. Its totient is φ = 168014905344.

The previous prime is 636945716731. The next prime is 636945716749. The reversal of 636945716736 is 637617549636.

It is a happy number.

636945716736 is a `hidden beast` number, since 63 + 69 + 457 + 1 + 67 + 3 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636945716731) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3814046125 + ... + 3814046291.

Almost surely, 2^636945716736 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 636945716736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1135061351424).

636945716736 is an abundant number, since it is smaller than the sum of its proper divisors (1633176986112).

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

636945716736 is a wasteful number, since it uses less digits than its factorization.

636945716736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 352 counting only the distinct ones).

The product of its digits is 102876480, while the sum is 63.

The spelling of 636945716736 in words is "six hundred thirty-six billion, nine hundred forty-five million, seven hundred sixteen thousand, seven hundred thirty-six".