21163223 has 8 divisors (see below), whose sum is σ = 22062192. Its totient is φ = 20281536.

The previous prime is 21163201. The next prime is 21163229. The reversal of 21163223 is 32236112.

It is a happy number.

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 21163223 - 2⁶ = 21163159 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21163195 and 21163204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21163229) 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, 1790 + ... + 6747.

It is an arithmetic number, because the mean of its divisors is an integer number (2757774).

It is a self-describing number.

Almost surely, 2^21163223 is an apocalyptic number.

21163223 is a deficient number, since it is larger than the sum of its proper divisors (898969).

21163223 is an equidigital number, since it uses as much as digits as its factorization.

21163223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8641.

The product of its digits is 432, while the sum is 20.

The square root of 21163223 is about 4600.3503127479. The cubic root of 21163223 is about 276.6053671389.

Adding to 21163223 its reverse (32236112), we get a palindrome (53399335).

The spelling of 21163223 in words is "twenty-one million, one hundred sixty-three thousand, two hundred twenty-three".