23200721 has 8 divisors (see below), whose sum is σ = 24266304. Its totient is φ = 22139920.

The previous prime is 23200717. The next prime is 23200753. The reversal of 23200721 is 12700232.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 23200721 - 2² = 23200717 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 23200721.

It is not an unprimeable number, because it can be changed into a prime (23200781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11906 + ... + 13716.

It is an arithmetic number, because the mean of its divisors is an integer number (3033288).

Almost surely, 2^23200721 is an apocalyptic number.

It is an amenable number.

23200721 is a deficient number, since it is larger than the sum of its proper divisors (1065583).

23200721 is a wasteful number, since it uses less digits than its factorization.

23200721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2391.

The product of its (nonzero) digits is 168, while the sum is 17.

The square root of 23200721 is about 4816.7126756741. The cubic root of 23200721 is about 285.2115839298.

Adding to 23200721 its reverse (12700232), we get a palindrome (35900953).

The spelling of 23200721 in words is "twenty-three million, two hundred thousand, seven hundred twenty-one".