644846113 has 2 divisors, whose sum is σ = 644846114. Its totient is φ = 644846112.

The previous prime is 644846107. The next prime is 644846179. The reversal of 644846113 is 311648446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 372991969 + 271854144 = 19313^2 + 16488^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-644846113 is a prime.

It is not a weakly prime, because it can be changed into another prime (644846513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322423056 + 322423057.

It is an arithmetic number, because the mean of its divisors is an integer number (322423057).

Almost surely, 2^644846113 is an apocalyptic number.

It is an amenable number.

644846113 is a deficient number, since it is larger than the sum of its proper divisors (1).

644846113 is an equidigital number, since it uses as much as digits as its factorization.

644846113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55296, while the sum is 37.

The square root of 644846113 is about 25393.8203703184. The cubic root of 644846113 is about 863.9435409959.

The spelling of 644846113 in words is "six hundred forty-four million, eight hundred forty-six thousand, one hundred thirteen".