2391491 has 2 divisors, whose sum is σ = 2391492. Its totient is φ = 2391490.

The previous prime is 2391469. The next prime is 2391503. The reversal of 2391491 is 1941932.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2391491 is a prime.

It is not a weakly prime, because it can be changed into another prime (2391401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1195745 + 1195746.

It is an arithmetic number, because the mean of its divisors is an integer number (1195746).

2^2391491 is an apocalyptic number.

2391491 is a deficient number, since it is larger than the sum of its proper divisors (1).

2391491 is an equidigital number, since it uses as much as digits as its factorization.

2391491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 29.

The square root of 2391491 is about 1546.4446320512. Note that the first 3 decimals coincide. The cubic root of 2391491 is about 133.7281747367.

It can be divided in two parts, 2391 and 491, that added together give a palindrome (2882).

The spelling of 2391491 in words is "two million, three hundred ninety-one thousand, four hundred ninety-one".