21292339 has 4 divisors (see below), whose sum is σ = 21402856. Its totient is φ = 21181824.

The previous prime is 21292309. The next prime is 21292343. The reversal of 21292339 is 93329212.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21292339 - 2⁵ = 21292307 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 21292339.

It is not an unprimeable number, because it can be changed into a prime (21292309) 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, 54969 + ... + 55354.

It is an arithmetic number, because the mean of its divisors is an integer number (5350714).

Almost surely, 2^21292339 is an apocalyptic number.

21292339 is a deficient number, since it is larger than the sum of its proper divisors (110517).

21292339 is a wasteful number, since it uses less digits than its factorization.

21292339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110516.

The product of its digits is 5832, while the sum is 31.

The square root of 21292339 is about 4614.3622527929. The cubic root of 21292339 is about 277.1667465578.

The spelling of 21292339 in words is "twenty-one million, two hundred ninety-two thousand, three hundred thirty-nine".