21293045 has 4 divisors (see below), whose sum is σ = 25551660. Its totient is φ = 17034432.

The previous prime is 21293039. The next prime is 21293057. The reversal of 21293045 is 54039212.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3912484 + 17380561 = 1978^2 + 4169^2 .

It is a cyclic number.

It is not a de Polignac number, because 21293045 - 2⁴ = 21293029 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2129300 + ... + 2129309.

It is an arithmetic number, because the mean of its divisors is an integer number (6387915).

Almost surely, 2^21293045 is an apocalyptic number.

It is an amenable number.

21293045 is a deficient number, since it is larger than the sum of its proper divisors (4258615).

21293045 is an equidigital number, since it uses as much as digits as its factorization.

21293045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4258614.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 21293045 is about 4614.4387524378. The cubic root of 21293045 is about 277.1698099062.

The spelling of 21293045 in words is "twenty-one million, two hundred ninety-three thousand, forty-five".