644101416 has 128 divisors (see below), whose sum is σ = 2052806400. Its totient is φ = 183306240.

The previous prime is 644101399. The next prime is 644101427. The reversal of 644101416 is 614101446.

644101416 is a `hidden beast` number, since 644 + 1 + 0 + 1 + 4 + 16 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 644101416.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 472576 + ... + 473936.

It is an arithmetic number, because the mean of its divisors is an integer number (16037550).

Almost surely, 2^644101416 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 644101416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1026403200).

644101416 is an abundant number, since it is smaller than the sum of its proper divisors (1408704984).

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

644101416 is a wasteful number, since it uses less digits than its factorization.

644101416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1696 (or 1686 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 644101416 is about 25379.1531773619. The cubic root of 644101416 is about 863.6108394021.

The spelling of 644101416 in words is "six hundred forty-four million, one hundred one thousand, four hundred sixteen".