644267227 has 2 divisors, whose sum is σ = 644267228. Its totient is φ = 644267226.

The previous prime is 644267213. The next prime is 644267231. The reversal of 644267227 is 722762446.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 644267227 - 2¹¹ = 644265179 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 644267227.

It is not a weakly prime, because it can be changed into another prime (644267627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322133613 + 322133614.

It is an arithmetic number, because the mean of its divisors is an integer number (322133614).

Almost surely, 2^644267227 is an apocalyptic number.

644267227 is a deficient number, since it is larger than the sum of its proper divisors (1).

644267227 is an equidigital number, since it uses as much as digits as its factorization.

644267227 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 40.

The square root of 644267227 is about 25382.4196443129. The cubic root of 644267227 is about 863.6849394778.

The spelling of 644267227 in words is "six hundred forty-four million, two hundred sixty-seven thousand, two hundred twenty-seven".