21322039 has 4 divisors (see below), whose sum is σ = 21335680. Its totient is φ = 21308400.

The previous prime is 21322031. The next prime is 21322043. The reversal of 21322039 is 93022312.

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 21322039 - 2³ = 21322031 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 (21322031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4119 + ... + 7720.

It is an arithmetic number, because the mean of its divisors is an integer number (5333920).

Almost surely, 2^21322039 is an apocalyptic number.

21322039 is a deficient number, since it is larger than the sum of its proper divisors (13641).

21322039 is a wasteful number, since it uses less digits than its factorization.

21322039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13640.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 21322039 is about 4617.5793442019. The cubic root of 21322039 is about 277.2955570169.

The spelling of 21322039 in words is "twenty-one million, three hundred twenty-two thousand, thirty-nine".