21883309 has 4 divisors (see below), whose sum is σ = 25009504. Its totient is φ = 18757116.

The previous prime is 21883273. The next prime is 21883321. The reversal of 21883309 is 90338812.

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 not a de Polignac number, because 21883309 - 2⁷ = 21883181 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 (21883349) 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, 1563087 + ... + 1563100.

It is an arithmetic number, because the mean of its divisors is an integer number (6252376).

Almost surely, 2^21883309 is an apocalyptic number.

It is an amenable number.

21883309 is a deficient number, since it is larger than the sum of its proper divisors (3126195).

21883309 is an equidigital number, since it uses as much as digits as its factorization.

21883309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3126194.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 21883309 is about 4677.9599185970. The cubic root of 21883309 is about 279.7076412719.

The spelling of 21883309 in words is "twenty-one million, eight hundred eighty-three thousand, three hundred nine".