644792094 has 48 divisors (see below), whose sum is σ = 1477179600. Its totient is φ = 202704768.

The previous prime is 644792089. The next prime is 644792131. The reversal of 644792094 is 490297446.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 74202 + ... + 82434.

It is an arithmetic number, because the mean of its divisors is an integer number (30774575).

Almost surely, 2^644792094 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 644792094, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (738589800).

644792094 is an abundant number, since it is smaller than the sum of its proper divisors (832387506).

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

644792094 is a wasteful number, since it uses less digits than its factorization.

644792094 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8489 (or 8486 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The square root of 644792094 is about 25392.7567231287. The cubic root of 644792094 is about 863.9194160311.

The spelling of 644792094 in words is "six hundred forty-four million, seven hundred ninety-two thousand, ninety-four".