2031391 has 2 divisors, whose sum is σ = 2031392. Its totient is φ = 2031390.

The previous prime is 2031353. The next prime is 2031397. The reversal of 2031391 is 1931302.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2031391 - 2⁹ = 2030879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2031397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1015695 + 1015696.

It is an arithmetic number, because the mean of its divisors is an integer number (1015696).

2^2031391 is an apocalyptic number.

2031391 is a deficient number, since it is larger than the sum of its proper divisors (1).

2031391 is an equidigital number, since it uses as much as digits as its factorization.

2031391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 2031391 is about 1425.2687465878. The cubic root of 2031391 is about 126.6478557785.

Adding to 2031391 its reverse (1931302), we get a palindrome (3962693).

The spelling of 2031391 in words is "two million, thirty-one thousand, three hundred ninety-one".