644880941 has 8 divisors (see below), whose sum is σ = 704841984. Its totient is φ = 587367360.

The previous prime is 644880889. The next prime is 644880953. The reversal of 644880941 is 149088446.

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

It is a cyclic number.

It is not a de Polignac number, because 644880941 - 2¹⁴ = 644864557 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 644880892 and 644880901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (644880991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 611315 + ... + 612368.

It is an arithmetic number, because the mean of its divisors is an integer number (88105248).

Almost surely, 2^644880941 is an apocalyptic number.

It is an amenable number.

644880941 is a deficient number, since it is larger than the sum of its proper divisors (59961043).

644880941 is a wasteful number, since it uses less digits than its factorization.

644880941 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223731.

The product of its (nonzero) digits is 221184, while the sum is 44.

The square root of 644880941 is about 25394.5061184501. The cubic root of 644880941 is about 863.9590945176.

The spelling of 644880941 in words is "six hundred forty-four million, eight hundred eighty thousand, nine hundred forty-one".