2391391391 has 2 divisors, whose sum is σ = 2391391392. Its totient is φ = 2391391390.

The previous prime is 2391391381. The next prime is 2391391427. The reversal of 2391391391 is 1931931932.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2391391391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2391391361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1195695695 + 1195695696.

It is an arithmetic number, because the mean of its divisors is an integer number (1195695696).

Almost surely, 2^2391391391 is an apocalyptic number.

2391391391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2391391391 is an equidigital number, since it uses as much as digits as its factorization.

2391391391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39366, while the sum is 41.

The square root of 2391391391 is about 48901.8546785293. The cubic root of 2391391391 is about 1337.2631805474.

The spelling of 2391391391 in words is "two billion, three hundred ninety-one million, three hundred ninety-one thousand, three hundred ninety-one".