21632223 has 16 divisors (see below), whose sum is σ = 29454336. Its totient is φ = 14118720.

The previous prime is 21632201. The next prime is 21632257. The reversal of 21632223 is 32223612.

It is not a de Polignac number, because 21632223 - 2⁹ = 21631711 is a prime.

It is a plaindrome in base 11.

It is a self number, because there is not a number n which added to its sum of digits gives 21632223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21632323) 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 15 ways as a sum of consecutive naturals, for example, 56290 + ... + 56672.

It is an arithmetic number, because the mean of its divisors is an integer number (1840896).

Almost surely, 2^21632223 is an apocalyptic number.

21632223 is a deficient number, since it is larger than the sum of its proper divisors (7822113).

21632223 is a wasteful number, since it uses less digits than its factorization.

21632223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734.

The product of its digits is 864, while the sum is 21.

The square root of 21632223 is about 4651.0453663666. The cubic root of 21632223 is about 278.6337481688.

Adding to 21632223 its reverse (32223612), we get a palindrome (53855835).

The spelling of 21632223 in words is "twenty-one million, six hundred thirty-two thousand, two hundred twenty-three".