636380774400 has 828 divisors, whose sum is σ = 2554699930208. Its totient is φ = 136902082560.

The previous prime is 636380774389. The next prime is 636380774479. The reversal of 636380774400 is 4477083636.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 636380774400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 37434163192 + ... + 37434163208.

Almost surely, 2^636380774400 is an apocalyptic number.

636380774400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 636380774400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1277349965104).

636380774400 is an abundant number, since it is smaller than the sum of its proper divisors (1918319155808).

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

636380774400 is an frugal number, since it uses more digits than its factorization.

636380774400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 34 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 48.

The spelling of 636380774400 in words is "six hundred thirty-six billion, three hundred eighty million, seven hundred seventy-four thousand, four hundred".