644980883 has 2 divisors, whose sum is σ = 644980884. Its totient is φ = 644980882.

The previous prime is 644980879. The next prime is 644980907. The reversal of 644980883 is 388089446.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 644980883 - 2² = 644980879 is a prime.

It is not a weakly prime, because it can be changed into another prime (644980873) 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 as a sum of consecutive naturals, namely, 322490441 + 322490442.

It is an arithmetic number, because the mean of its divisors is an integer number (322490442).

Almost surely, 2^644980883 is an apocalyptic number.

644980883 is a deficient number, since it is larger than the sum of its proper divisors (1).

644980883 is an equidigital number, since it uses as much as digits as its factorization.

644980883 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1327104, while the sum is 50.

The square root of 644980883 is about 25396.4738300418. The cubic root of 644980883 is about 864.0037236029.

The spelling of 644980883 in words is "six hundred forty-four million, nine hundred eighty thousand, eight hundred eighty-three".