21223441 has 4 divisors (see below), whose sum is σ = 21385584. Its totient is φ = 21061300.

The previous prime is 21223427. The next prime is 21223453. The reversal of 21223441 is 14432212.

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 21223441 - 2⁵ = 21223409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21223141) 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, 80875 + ... + 81136.

It is an arithmetic number, because the mean of its divisors is an integer number (5346396).

Almost surely, 2^21223441 is an apocalyptic number.

It is an amenable number.

21223441 is a deficient number, since it is larger than the sum of its proper divisors (162143).

21223441 is a wasteful number, since it uses less digits than its factorization.

21223441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162142.

The product of its digits is 384, while the sum is 19.

The square root of 21223441 is about 4606.8905999600. The cubic root of 21223441 is about 276.8674703896.

Adding to 21223441 its reverse (14432212), we get a palindrome (35655653).

It can be divided in two parts, 212 and 23441, that added together give a triangular number (23653 = T₂₁₇).

The spelling of 21223441 in words is "twenty-one million, two hundred twenty-three thousand, four hundred forty-one".