249453021 has 4 divisors (see below), whose sum is σ = 332604032. Its totient is φ = 166302012.

The previous prime is 249453013. The next prime is 249453047. The reversal of 249453021 is 120354942.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 249453021 - 2³ = 249453013 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 249453021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249453091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41575501 + ... + 41575506.

It is an arithmetic number, because the mean of its divisors is an integer number (83151008).

Almost surely, 2^249453021 is an apocalyptic number.

It is an amenable number.

249453021 is a deficient number, since it is larger than the sum of its proper divisors (83151011).

249453021 is an equidigital number, since it uses as much as digits as its factorization.

249453021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83151010.

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 249453021 is about 15794.0818346620. The cubic root of 249453021 is about 629.5007559016.

It can be divided in two parts, 24945 and 3021, that added together give a triangular number (27966 = T₂₃₆).

The spelling of 249453021 in words is "two hundred forty-nine million, four hundred fifty-three thousand, twenty-one".