644002160208 has 80 divisors (see below), whose sum is σ = 1815579480000. Its totient is φ = 195080739840.

The previous prime is 644002160173. The next prime is 644002160213. The reversal of 644002160208 is 802061200446.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1229628 + ... + 1673316.

It is an arithmetic number, because the mean of its divisors is an integer number (22694743500).

Almost surely, 2^644002160208 is an apocalyptic number.

It is an amenable number.

644002160208 is an abundant number, since it is smaller than the sum of its proper divisors (1171577319792).

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

644002160208 is a wasteful number, since it uses less digits than its factorization.

644002160208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 446460 (or 446454 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The spelling of 644002160208 in words is "six hundred forty-four billion, two million, one hundred sixty thousand, two hundred eight".