644210848512 has 720 divisors, whose sum is σ = 2428159759872. Its totient is φ = 165005475840.

The previous prime is 644210848511. The next prime is 644210848513. The reversal of 644210848512 is 215848012446.

644210848512 is a `hidden beast` number, since 6 + 4 + 42 + 10 + 84 + 8 + 512 = 666.

It is an interprime number because it is at equal distance from previous prime (644210848511) and next prime (644210848513).

It is a super-2 number, since 2×644210848512² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (644210848511) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 116554293 + ... + 116559819.

Almost surely, 2^644210848512 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 644210848512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1214079879936).

644210848512 is an abundant number, since it is smaller than the sum of its proper divisors (1783948911360).

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

644210848512 is a wasteful number, since it uses less digits than its factorization.

644210848512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5646 (or 5623 counting only the distinct ones).

The product of its (nonzero) digits is 491520, while the sum is 45.

The spelling of 644210848512 in words is "six hundred forty-four billion, two hundred ten million, eight hundred forty-eight thousand, five hundred twelve".