636873560064 has 1248 divisors, whose sum is σ = 2438648110080. Its totient is φ = 161673117696.

The previous prime is 636873560051. The next prime is 636873560069. The reversal of 636873560064 is 460065378636.

636873560064 is a `hidden beast` number, since 6 + 3 + 6 + 8 + 73 + 560 + 0 + 6 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (636873560069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2250436467 + ... + 2250436749.

It is an arithmetic number, because the mean of its divisors is an integer number (1954044960).

Almost surely, 2^636873560064 is an apocalyptic number.

636873560064 is a gapful number since it is divisible by the number (64) 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 636873560064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1219324055040).

636873560064 is an abundant number, since it is smaller than the sum of its proper divisors (1801774550016).

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

636873560064 is a wasteful number, since it uses less digits than its factorization.

636873560064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365 (or 331 counting only the distinct ones).

The product of its (nonzero) digits is 13063680, while the sum is 54.

The spelling of 636873560064 in words is "six hundred thirty-six billion, eight hundred seventy-three million, five hundred sixty thousand, sixty-four".