391917013 has 2 divisors, whose sum is σ = 391917014. Its totient is φ = 391917012.

The previous prime is 391916989. The next prime is 391917017. The reversal of 391917013 is 310719193.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 258791569 + 133125444 = 16087^2 + 11538^2 .

It is a cyclic number.

It is not a de Polignac number, because 391917013 - 2⁵ = 391916981 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 391917013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (391917017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195958506 + 195958507.

It is an arithmetic number, because the mean of its divisors is an integer number (195958507).

Almost surely, 2^391917013 is an apocalyptic number.

It is an amenable number.

391917013 is a deficient number, since it is larger than the sum of its proper divisors (1).

391917013 is an equidigital number, since it uses as much as digits as its factorization.

391917013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5103, while the sum is 34.

The square root of 391917013 is about 19796.8940240635. The cubic root of 391917013 is about 731.8094929850.

The spelling of 391917013 in words is "three hundred ninety-one million, nine hundred seventeen thousand, thirteen".