391323161 has 2 divisors, whose sum is σ = 391323162. Its totient is φ = 391323160.

The previous prime is 391323157. The next prime is 391323193. The reversal of 391323161 is 161323193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 383376400 + 7946761 = 19580^2 + 2819^2 .

It is a cyclic number.

It is not a de Polignac number, because 391323161 - 2² = 391323157 is a prime.

It is not a weakly prime, because it can be changed into another prime (391323661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195661580 + 195661581.

It is an arithmetic number, because the mean of its divisors is an integer number (195661581).

Almost surely, 2^391323161 is an apocalyptic number.

It is an amenable number.

391323161 is a deficient number, since it is larger than the sum of its proper divisors (1).

391323161 is an equidigital number, since it uses as much as digits as its factorization.

391323161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2916, while the sum is 29.

The square root of 391323161 is about 19781.8897226731. The cubic root of 391323161 is about 731.4396815166.

The spelling of 391323161 in words is "three hundred ninety-one million, three hundred twenty-three thousand, one hundred sixty-one".