12991679 has 2 divisors, whose sum is σ = 12991680. Its totient is φ = 12991678.

The previous prime is 12991673. The next prime is 12991703. The reversal of 12991679 is 97619921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12991679 - 2⁸ = 12991423 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12991673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6495839 + 6495840.

It is an arithmetic number, because the mean of its divisors is an integer number (6495840).

Almost surely, 2^12991679 is an apocalyptic number.

12991679 is a deficient number, since it is larger than the sum of its proper divisors (1).

12991679 is an equidigital number, since it uses as much as digits as its factorization.

12991679 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 44.

The square root of 12991679 is about 3604.3971756731. The cubic root of 12991679 is about 235.0832902288.

The spelling of 12991679 in words is "twelve million, nine hundred ninety-one thousand, six hundred seventy-nine".