644516127360 has 2048 divisors, whose sum is σ = 2918799360000. Its totient is φ = 131032940544.

The previous prime is 644516127349. The next prime is 644516127377. The reversal of 644516127360 is 63721615446.

644516127360 is a `hidden beast` number, since 6 + 4 + 4 + 516 + 1 + 2 + 73 + 60 = 666.

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

It is an unprimeable number.

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 255 ways as a sum of consecutive naturals, for example, 4704497212 + ... + 4704497348.

It is an arithmetic number, because the mean of its divisors is an integer number (1425195000).

Almost surely, 2^644516127360 is an apocalyptic number.

644516127360 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 644516127360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1459399680000).

644516127360 is an abundant number, since it is smaller than the sum of its proper divisors (2274283232640).

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

644516127360 is a wasteful number, since it uses less digits than its factorization.

644516127360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303 (or 285 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 644516127360 in words is "six hundred forty-four billion, five hundred sixteen million, one hundred twenty-seven thousand, three hundred sixty".