21488223 has 12 divisors (see below), whose sum is σ = 29373704. Its totient is φ = 13972800.

The previous prime is 21488209. The next prime is 21488263. The reversal of 21488223 is 32288412.

It is not a de Polignac number, because 21488223 - 2¹⁴ = 21471839 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 (21488263) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2913 + ... + 7173.

Almost surely, 2^21488223 is an apocalyptic number.

21488223 is a deficient number, since it is larger than the sum of its proper divisors (7885481).

21488223 is an equidigital number, since it uses as much as digits as its factorization.

21488223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4346 (or 4305 counting only the distinct ones).

The product of its digits is 6144, while the sum is 30.

The square root of 21488223 is about 4635.5391272213. The cubic root of 21488223 is about 278.0141074220.

The spelling of 21488223 in words is "twenty-one million, four hundred eighty-eight thousand, two hundred twenty-three".