679669 has 2 divisors, whose sum is σ = 679670. Its totient is φ = 679668.

The previous prime is 679639. The next prime is 679681. The reversal of 679669 is 966976.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 439569 + 240100 = 663^2 + 490^2 .

It is a cyclic number.

It is not a de Polignac number, because 679669 - 2⁹ = 679157 is a prime.

It is a super-2 number, since 2×679669² = 923899899122, which contains 22 as substring.

It is a plaindrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (679639) by changing a digit.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 339834 + 339835.

It is an arithmetic number, because the mean of its divisors is an integer number (339835).

2⁶⁷⁹⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

679669 is a deficient number, since it is larger than the sum of its proper divisors (1).

679669 is an equidigital number, since it uses as much as digits as its factorization.

679669 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 122472, while the sum is 43.

The square root of 679669 is about 824.4204024647. The cubic root of 679669 is about 87.9223229841.

The spelling of 679669 in words is "six hundred seventy-nine thousand, six hundred sixty-nine".