669659 has 2 divisors, whose sum is σ = 669660. Its totient is φ = 669658.

The previous prime is 669649. The next prime is 669661. The reversal of 669659 is 956966.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 669659 - 2¹² = 665563 is a prime.

Together with 669661, it forms a pair of twin primes.

It is a Chen prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 669659.

It is not a weakly prime, because it can be changed into another prime (669649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334829 + 334830.

It is an arithmetic number, because the mean of its divisors is an integer number (334830).

2⁶⁶⁹⁶⁵⁹ is an apocalyptic number.

669659 is a deficient number, since it is larger than the sum of its proper divisors (1).

669659 is an equidigital number, since it uses as much as digits as its factorization.

669659 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 87480, while the sum is 41.

The square root of 669659 is about 818.3269517742. The cubic root of 669659 is about 87.4885536047.

The spelling of 669659 in words is "six hundred sixty-nine thousand, six hundred fifty-nine".