2391391 has 4 divisors (see below), whose sum is σ = 2394832. Its totient is φ = 2387952.

The previous prime is 2391349. The next prime is 2391401. The reversal of 2391391 is 1931932.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2391391 - 2⁹ = 2390879 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2391331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270 + ... + 2203.

It is an arithmetic number, because the mean of its divisors is an integer number (598708).

2^2391391 is an apocalyptic number.

2391391 is a deficient number, since it is larger than the sum of its proper divisors (3441).

2391391 is an equidigital number, since it uses as much as digits as its factorization.

2391391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3440.

The product of its digits is 1458, while the sum is 28.

The square root of 2391391 is about 1546.4122994855. The cubic root of 2391391 is about 133.7263107665.

The spelling of 2391391 in words is "two million, three hundred ninety-one thousand, three hundred ninety-one".