23705221 has 4 divisors (see below), whose sum is σ = 23716000. Its totient is φ = 23694444.

The previous prime is 23705219. The next prime is 23705233. The reversal of 23705221 is 12250732.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 23705221 - 2¹ = 23705219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23705192 and 23705201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23705261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 771 + ... + 6928.

It is an arithmetic number, because the mean of its divisors is an integer number (5929000).

Almost surely, 2^23705221 is an apocalyptic number.

It is an amenable number.

23705221 is a deficient number, since it is larger than the sum of its proper divisors (10779).

23705221 is an equidigital number, since it uses as much as digits as its factorization.

23705221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10778.

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 23705221 is about 4868.8007763719. The cubic root of 23705221 is about 287.2640877572.

Adding to 23705221 its reverse (12250732), we get a palindrome (35955953).

The spelling of 23705221 in words is "twenty-three million, seven hundred five thousand, two hundred twenty-one".