23217729 has 16 divisors (see below), whose sum is σ = 32085504. Its totient is φ = 14918400.

The previous prime is 23217713. The next prime is 23217731. The reversal of 23217729 is 92771232.

It is not a de Polignac number, because 23217729 - 2⁴ = 23217713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 23217729.

It is not an unprimeable number, because it can be changed into a prime (23217709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38857 + ... + 39449.

It is an arithmetic number, because the mean of its divisors is an integer number (2005344).

Almost surely, 2^23217729 is an apocalyptic number.

It is an amenable number.

23217729 is a deficient number, since it is larger than the sum of its proper divisors (8867775).

23217729 is a wasteful number, since it uses less digits than its factorization.

23217729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1048.

The product of its digits is 10584, while the sum is 33.

The square root of 23217729 is about 4818.4778716935. The cubic root of 23217729 is about 285.2812612722.

The spelling of 23217729 in words is "twenty-three million, two hundred seventeen thousand, seven hundred twenty-nine".