4042391 has 2 divisors, whose sum is σ = 4042392. Its totient is φ = 4042390.

The previous prime is 4042343. The next prime is 4042393. The reversal of 4042391 is 1932404.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 4042391 - 2⁶ = 4042327 is a prime.

Together with 4042393, 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 (4042393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2021195 + 2021196.

It is an arithmetic number, because the mean of its divisors is an integer number (2021196).

Almost surely, 2^4042391 is an apocalyptic number.

4042391 is a deficient number, since it is larger than the sum of its proper divisors (1).

4042391 is an equidigital number, since it uses as much as digits as its factorization.

4042391 is an odious number, because the sum of its binary digits is odd.

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

The square root of 4042391 is about 2010.5698197277. The cubic root of 4042391 is about 159.2988984873.

Adding to 4042391 its reverse (1932404), we get a palindrome (5974795).

The spelling of 4042391 in words is "four million, forty-two thousand, three hundred ninety-one".