664879 has 2 divisors, whose sum is σ = 664880. Its totient is φ = 664878.

The previous prime is 664849. The next prime is 664891. The reversal of 664879 is 978466.

664879 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664879 - 2⁵ = 664847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664849) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332439 + 332440.

It is an arithmetic number, because the mean of its divisors is an integer number (332440).

2⁶⁶⁴⁸⁷⁹ is an apocalyptic number.

664879 is a deficient number, since it is larger than the sum of its proper divisors (1).

664879 is an equidigital number, since it uses as much as digits as its factorization.

664879 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 40.

The square root of 664879 is about 815.4011282798. The cubic root of 664879 is about 87.2798930419.

The spelling of 664879 in words is "six hundred sixty-four thousand, eight hundred seventy-nine".