669859 has 2 divisors, whose sum is σ = 669860. Its totient is φ = 669858.

The previous prime is 669857. The next prime is 669863. The reversal of 669859 is 958966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669859 - 2¹ = 669857 is a prime.

It is a super-2 number, since 2×669859² = 897422159762, which contains 22 as substring.

Together with 669857, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (669853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334929 + 334930.

It is an arithmetic number, because the mean of its divisors is an integer number (334930).

2⁶⁶⁹⁸⁵⁹ is an apocalyptic number.

669859 is a deficient number, since it is larger than the sum of its proper divisors (1).

669859 is an equidigital number, since it uses as much as digits as its factorization.

669859 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 116640, while the sum is 43.

The square root of 669859 is about 818.4491431971. The cubic root of 669859 is about 87.4972624994.

The spelling of 669859 in words is "six hundred sixty-nine thousand, eight hundred fifty-nine".