249789491 has 4 divisors (see below), whose sum is σ = 285473712. Its totient is φ = 214105272.

The previous prime is 249789487. The next prime is 249789503. The reversal of 249789491 is 194987942.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194987942 = 2 ⋅97493971.

It is a cyclic number.

It is not a de Polignac number, because 249789491 - 2² = 249789487 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (249789401) 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 in 3 ways as a sum of consecutive naturals, for example, 17842100 + ... + 17842113.

It is an arithmetic number, because the mean of its divisors is an integer number (71368428).

Almost surely, 2^249789491 is an apocalyptic number.

249789491 is a deficient number, since it is larger than the sum of its proper divisors (35684221).

249789491 is an equidigital number, since it uses as much as digits as its factorization.

249789491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35684220.

The product of its digits is 1306368, while the sum is 53.

The square root of 249789491 is about 15804.7300198390. The cubic root of 249789491 is about 629.7836588154.

The spelling of 249789491 in words is "two hundred forty-nine million, seven hundred eighty-nine thousand, four hundred ninety-one".