22309 has 4 divisors (see below), whose sum is σ = 25504. Its totient is φ = 19116.

The previous prime is 22307. The next prime is 22343. The reversal of 22309 is 90322.

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 an emirpimes, since its reverse is a distinct semiprime: 90322 = 2 ⋅45161.

It is a cyclic number.

It is not a de Polignac number, because 22309 - 2¹ = 22307 is a prime.

It is a super-3 number, since 3×22309³ = 33308997748887, which contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22292 and 22301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22303) 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, 1587 + ... + 1600.

It is an arithmetic number, because the mean of its divisors is an integer number (6376).

2²²³⁰⁹ is an apocalyptic number.

It is an amenable number.

22309 is a deficient number, since it is larger than the sum of its proper divisors (3195).

22309 is an equidigital number, since it uses as much as digits as its factorization.

22309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3194.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 22309 is about 149.3619764197. The cubic root of 22309 is about 28.1509702507.

Subtracting from 22309 its product of nonzero digits (108), we obtain a square (22201 = 149²).

The spelling of 22309 in words is "twenty-two thousand, three hundred nine".