666679031 has 2 divisors, whose sum is σ = 666679032. Its totient is φ = 666679030.

The previous prime is 666679019. The next prime is 666679033. The reversal of 666679031 is 130976666.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666679031 is a prime.

It is a super-2 number, since 2×666679031² = 888921860750197922, which contains 22 as substring.

Together with 666679033, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666679033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333339515 + 333339516.

It is an arithmetic number, because the mean of its divisors is an integer number (333339516).

Almost surely, 2^666679031 is an apocalyptic number.

666679031 is a deficient number, since it is larger than the sum of its proper divisors (1).

666679031 is an equidigital number, since it uses as much as digits as its factorization.

666679031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 244944, while the sum is 44.

The square root of 666679031 is about 25820.1284078914. The cubic root of 666679031 is about 873.5858653229.

The spelling of 666679031 in words is "six hundred sixty-six million, six hundred seventy-nine thousand, thirty-one".