21201320223 has 6 divisors (see below), whose sum is σ = 30624129224. Its totient is φ = 14134213476.

The previous prime is 21201320207. The next prime is 21201320233. The reversal of 21201320223 is 32202310212.

21201320223 is a `hidden beast` number, since 2 + 120 + 1 + 320 + 223 = 666.

It is not a de Polignac number, because 21201320223 - 2⁴ = 21201320207 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201320196 and 21201320205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201320233) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1177851115 + ... + 1177851132.

Almost surely, 2^21201320223 is an apocalyptic number.

21201320223 is a deficient number, since it is larger than the sum of its proper divisors (9422809001).

21201320223 is a wasteful number, since it uses less digits than its factorization.

21201320223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2355702253 (or 2355702250 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21201320223 its reverse (32202310212), we get a palindrome (53403630435).

The spelling of 21201320223 in words is "twenty-one billion, two hundred one million, three hundred twenty thousand, two hundred twenty-three".