23220309 has 32 divisors (see below), whose sum is σ = 36691200. Its totient is φ = 12787200.

The previous prime is 23220289. The next prime is 23220313. The reversal of 23220309 is 90302232.

It is not a de Polignac number, because 23220309 - 2⁵ = 23220277 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23220319) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 128199 + ... + 128379.

It is an arithmetic number, because the mean of its divisors is an integer number (1146600).

Almost surely, 2^23220309 is an apocalyptic number.

It is an amenable number.

23220309 is a deficient number, since it is larger than the sum of its proper divisors (13470891).

23220309 is a wasteful number, since it uses less digits than its factorization.

23220309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381.

The product of its (nonzero) digits is 648, while the sum is 21.

The square root of 23220309 is about 4818.7455836556. The cubic root of 23220309 is about 285.2918278869.

The spelling of 23220309 in words is "twenty-three million, two hundred twenty thousand, three hundred nine".