391390193 has 2 divisors, whose sum is σ = 391390194. Its totient is φ = 391390192.

The previous prime is 391390189. The next prime is 391390211. The reversal of 391390193 is 391093193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 391367089 + 23104 = 19783^2 + 152^2 .

It is a cyclic number.

It is not a de Polignac number, because 391390193 - 2² = 391390189 is a prime.

It is not a weakly prime, because it can be changed into another prime (391390093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 195695096 + 195695097.

It is an arithmetic number, because the mean of its divisors is an integer number (195695097).

Almost surely, 2^391390193 is an apocalyptic number.

It is an amenable number.

391390193 is a deficient number, since it is larger than the sum of its proper divisors (1).

391390193 is an equidigital number, since it uses as much as digits as its factorization.

391390193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19683, while the sum is 38.

The square root of 391390193 is about 19783.5839270846. The cubic root of 391390193 is about 731.4814433052.

The spelling of 391390193 in words is "three hundred ninety-one million, three hundred ninety thousand, one hundred ninety-three".