644812374 has 8 divisors (see below), whose sum is σ = 1289624760. Its totient is φ = 214937456.

The previous prime is 644812373. The next prime is 644812393. The reversal of 644812374 is 473218446.

It is a sphenic number, since it is the product of 3 distinct primes.

644812374 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644812373) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53734359 + ... + 53734370.

It is an arithmetic number, because the mean of its divisors is an integer number (161203095).

Almost surely, 2^644812374 is an apocalyptic number.

644812374 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

644812374 is a wasteful number, since it uses less digits than its factorization.

644812374 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107468734.

The product of its digits is 129024, while the sum is 39.

The square root of 644812374 is about 25393.1560464626. The cubic root of 644812374 is about 863.9284732669.

The spelling of 644812374 in words is "six hundred forty-four million, eight hundred twelve thousand, three hundred seventy-four".