21282293 has 4 divisors (see below), whose sum is σ = 21294240. Its totient is φ = 21270348.

The previous prime is 21282269. The next prime is 21282301. The reversal of 21282293 is 39228212.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21282293 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 (21282253) 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, 2705 + ... + 7062.

It is an arithmetic number, because the mean of its divisors is an integer number (5323560).

Almost surely, 2^21282293 is an apocalyptic number.

It is an amenable number.

21282293 is a deficient number, since it is larger than the sum of its proper divisors (11947).

21282293 is an equidigital number, since it uses as much as digits as its factorization.

21282293 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11946.

The product of its digits is 3456, while the sum is 29.

The square root of 21282293 is about 4613.2735665685. The cubic root of 21282293 is about 277.1231494193.

The spelling of 21282293 in words is "twenty-one million, two hundred eighty-two thousand, two hundred ninety-three".