21201223 has 8 divisors (see below), whose sum is σ = 21792960. Its totient is φ = 20613120.

The previous prime is 21201209. The next prime is 21201251. The reversal of 21201223 is 32210212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21201223 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201203) 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, 14343 + ... + 15751.

It is an arithmetic number, because the mean of its divisors is an integer number (2724120).

Almost surely, 2^21201223 is an apocalyptic number.

21201223 is a deficient number, since it is larger than the sum of its proper divisors (591737).

21201223 is a wasteful number, since it uses less digits than its factorization.

21201223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1817.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21201223 is about 4604.4785806864. The cubic root of 21201223 is about 276.7708227053.

Adding to 21201223 its reverse (32210212), we get a palindrome (53411435).

The spelling of 21201223 in words is "twenty-one million, two hundred one thousand, two hundred twenty-three".