644046707 has 2 divisors, whose sum is σ = 644046708. Its totient is φ = 644046706.

The previous prime is 644046701. The next prime is 644046709. The reversal of 644046707 is 707640446.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644046707 - 2⁴ = 644046691 is a prime.

Together with 644046709, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (644046701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322023353 + 322023354.

It is an arithmetic number, because the mean of its divisors is an integer number (322023354).

Almost surely, 2^644046707 is an apocalyptic number.

644046707 is a deficient number, since it is larger than the sum of its proper divisors (1).

644046707 is an equidigital number, since it uses as much as digits as its factorization.

644046707 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112896, while the sum is 38.

The square root of 644046707 is about 25378.0753210325. The cubic root of 644046707 is about 863.5863874437.

The spelling of 644046707 in words is "six hundred forty-four million, forty-six thousand, seven hundred seven".