667956689 has 2 divisors, whose sum is σ = 667956690. Its totient is φ = 667956688.

The previous prime is 667956683. The next prime is 667956697. The reversal of 667956689 is 986659766.

667956689 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 469372225 + 198584464 = 21665^2 + 14092^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667956689 is a prime.

It is a super-2 number, since 2×667956689² = 892332276759685442, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (667956683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333978344 + 333978345.

It is an arithmetic number, because the mean of its divisors is an integer number (333978345).

Almost surely, 2^667956689 is an apocalyptic number.

It is an amenable number.

667956689 is a deficient number, since it is larger than the sum of its proper divisors (1).

667956689 is an equidigital number, since it uses as much as digits as its factorization.

667956689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29393280, while the sum is 62.

The square root of 667956689 is about 25844.8580766078. The cubic root of 667956689 is about 874.1435708373.

The spelling of 667956689 in words is "six hundred sixty-seven million, nine hundred fifty-six thousand, six hundred eighty-nine".