23535721 has 4 divisors (see below), whose sum is σ = 25675344. Its totient is φ = 21396100.

The previous prime is 23535697. The next prime is 23535731. The reversal of 23535721 is 12753532.

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.

It is not a de Polignac number, because 23535721 - 2⁵ = 23535689 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 23535721.

It is not an unprimeable number, because it can be changed into a prime (23535731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1069795 + ... + 1069816.

It is an arithmetic number, because the mean of its divisors is an integer number (6418836).

Almost surely, 2^23535721 is an apocalyptic number.

It is an amenable number.

23535721 is a deficient number, since it is larger than the sum of its proper divisors (2139623).

23535721 is a wasteful number, since it uses less digits than its factorization.

23535721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2139622.

The product of its digits is 6300, while the sum is 28.

The square root of 23535721 is about 4851.3627982248. The cubic root of 23535721 is about 286.5777722988.

The spelling of 23535721 in words is "twenty-three million, five hundred thirty-five thousand, seven hundred twenty-one".