249481021 has 4 divisors (see below), whose sum is σ = 249573952. Its totient is φ = 249388092.

The previous prime is 249480991. The next prime is 249481049. The reversal of 249481021 is 120184942.

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 a cyclic number.

It is not a de Polignac number, because 249481021 - 2¹⁷ = 249349949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (249481081) 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, 42315 + ... + 47848.

It is an arithmetic number, because the mean of its divisors is an integer number (62393488).

Almost surely, 2^249481021 is an apocalyptic number.

It is an amenable number.

249481021 is a deficient number, since it is larger than the sum of its proper divisors (92931).

249481021 is an equidigital number, since it uses as much as digits as its factorization.

249481021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92930.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 249481021 is about 15794.9682177585. The cubic root of 249481021 is about 629.5243079137.

The spelling of 249481021 in words is "two hundred forty-nine million, four hundred eighty-one thousand, twenty-one".