21224489 has 24 divisors (see below), whose sum is σ = 25561536. Its totient is φ = 17503200.

The previous prime is 21224479. The next prime is 21224503. The reversal of 21224489 is 98442212.

It is a happy number.

It is not a de Polignac number, because 21224489 - 2¹² = 21220393 is a prime.

It is a super-2 number, since 2×21224489² = 900957866622242, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21224479) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 161954 + ... + 162084.

It is an arithmetic number, because the mean of its divisors is an integer number (1065064).

Almost surely, 2^21224489 is an apocalyptic number.

It is an amenable number.

21224489 is a deficient number, since it is larger than the sum of its proper divisors (4337047).

21224489 is a wasteful number, since it uses less digits than its factorization.

21224489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 258 counting only the distinct ones).

The product of its digits is 9216, while the sum is 32.

The square root of 21224489 is about 4607.0043412178. The cubic root of 21224489 is about 276.8720274943.

The spelling of 21224489 in words is "twenty-one million, two hundred twenty-four thousand, four hundred eighty-nine".