23212809 has 6 divisors (see below), whose sum is σ = 33529626. Its totient is φ = 15475200.

The previous prime is 23212771. The next prime is 23212823. The reversal of 23212809 is 90821232.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 11923209 + 11289600 = 3453^2 + 3360^2 .

It is not a de Polignac number, because 23212809 - 2⁹ = 23212297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (23212009) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1289592 + ... + 1289609.

It is an arithmetic number, because the mean of its divisors is an integer number (5588271).

Almost surely, 2^23212809 is an apocalyptic number.

It is an amenable number.

23212809 is a deficient number, since it is larger than the sum of its proper divisors (10316817).

23212809 is a wasteful number, since it uses less digits than its factorization.

23212809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2579207 (or 2579204 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 23212809 is about 4817.9673099763. The cubic root of 23212809 is about 285.2611088137.

It can be divided in two parts, 232 and 12809, that added together give a triangular number (13041 = T₁₆₁).

The spelling of 23212809 in words is "twenty-three million, two hundred twelve thousand, eight hundred nine".