2440391 has 2 divisors, whose sum is σ = 2440392. Its totient is φ = 2440390.

The previous prime is 2440387. The next prime is 2440393. The reversal of 2440391 is 1930442.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2440391 - 2² = 2440387 is a prime.

Together with 2440393, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2440393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1220195 + 1220196.

It is an arithmetic number, because the mean of its divisors is an integer number (1220196).

2^2440391 is an apocalyptic number.

2440391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2440391 is an equidigital number, since it uses as much as digits as its factorization.

2440391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 2440391 is about 1562.1750862179. The cubic root of 2440391 is about 134.6335006660.

The spelling of 2440391 in words is "two million, four hundred forty thousand, three hundred ninety-one".