23217221 has 4 divisors (see below), whose sum is σ = 24439200. Its totient is φ = 21995244.

The previous prime is 23217211. The next prime is 23217247. The reversal of 23217221 is 12271232.

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 a cyclic number.

It is not a de Polignac number, because 23217221 - 2²² = 19022917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 23217193 and 23217202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23217211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 610961 + ... + 610998.

It is an arithmetic number, because the mean of its divisors is an integer number (6109800).

Almost surely, 2^23217221 is an apocalyptic number.

It is an amenable number.

23217221 is a deficient number, since it is larger than the sum of its proper divisors (1221979).

23217221 is a wasteful number, since it uses less digits than its factorization.

23217221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1221978.

The product of its digits is 336, while the sum is 20.

The square root of 23217221 is about 4818.4251576630. The cubic root of 23217221 is about 285.2791806217.

Adding to 23217221 its reverse (12271232), we get a palindrome (35488453).

The spelling of 23217221 in words is "twenty-three million, two hundred seventeen thousand, two hundred twenty-one".