644614437376 has 160 divisors (see below), whose sum is σ = 1597309515648. Its totient is φ = 253063249920.

The previous prime is 644614437349. The next prime is 644614437419. The reversal of 644614437376 is 673734416446.

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, 6050746 + ... + 6156358.

Almost surely, 2^644614437376 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 644614437376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (798654757824).

644614437376 is an abundant number, since it is smaller than the sum of its proper divisors (952695078272).

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

644614437376 is a wasteful number, since it uses less digits than its factorization.

644614437376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105782 (or 105766 counting only the distinct ones).

The product of its digits is 24385536, while the sum is 55.

The spelling of 644614437376 in words is "six hundred forty-four billion, six hundred fourteen million, four hundred thirty-seven thousand, three hundred seventy-six".