391316729 has 2 divisors, whose sum is σ = 391316730. Its totient is φ = 391316728.

The previous prime is 391316711. The next prime is 391316741. The reversal of 391316729 is 927613193.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 371718400 + 19598329 = 19280^2 + 4427^2 .

It is a cyclic number.

It is not a de Polignac number, because 391316729 - 2⁸ = 391316473 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (391316929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195658364 + 195658365.

It is an arithmetic number, because the mean of its divisors is an integer number (195658365).

Almost surely, 2^391316729 is an apocalyptic number.

It is an amenable number.

391316729 is a deficient number, since it is larger than the sum of its proper divisors (1).

391316729 is an equidigital number, since it uses as much as digits as its factorization.

391316729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 41.

The square root of 391316729 is about 19781.7271490636. The cubic root of 391316729 is about 731.4356740480.

The spelling of 391316729 in words is "three hundred ninety-one million, three hundred sixteen thousand, seven hundred twenty-nine".