645885223 has 2 divisors, whose sum is σ = 645885224. Its totient is φ = 645885222.

The previous prime is 645885197. The next prime is 645885257. The reversal of 645885223 is 322588546.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 645885223 - 2⁹ = 645884711 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645885223.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645885623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322942611 + 322942612.

It is an arithmetic number, because the mean of its divisors is an integer number (322942612).

Almost surely, 2^645885223 is an apocalyptic number.

645885223 is a deficient number, since it is larger than the sum of its proper divisors (1).

645885223 is an equidigital number, since it uses as much as digits as its factorization.

645885223 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 460800, while the sum is 43.

The square root of 645885223 is about 25414.2720336428. The cubic root of 645885223 is about 864.4073470533.

The spelling of 645885223 in words is "six hundred forty-five million, eight hundred eighty-five thousand, two hundred twenty-three".