2491023 has 4 divisors (see below), whose sum is σ = 3321368. Its totient is φ = 1660680.

The previous prime is 2491009. The next prime is 2491031. The reversal of 2491023 is 3201942.

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

It is not a de Polignac number, because 2491023 - 2⁴ = 2491007 is a prime.

It is a D-number.

It is a Duffinian number.

2491023 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2491043) 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, 415168 + ... + 415173.

It is an arithmetic number, because the mean of its divisors is an integer number (830342).

2^2491023 is an apocalyptic number.

2491023 is a deficient number, since it is larger than the sum of its proper divisors (830345).

2491023 is an equidigital number, since it uses as much as digits as its factorization.

2491023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 830344.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 2491023 is about 1578.2975004732. The cubic root of 2491023 is about 135.5582371542.

Adding to 2491023 its reverse (3201942), we get a palindrome (5692965).

The spelling of 2491023 in words is "two million, four hundred ninety-one thousand, twenty-three".