21223024 has 20 divisors (see below), whose sum is σ = 41280840. Its totient is φ = 10569920.

The previous prime is 21223009. The next prime is 21223051. The reversal of 21223024 is 42032212.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21222989 and 21223007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1839 + ... + 6769.

It is an arithmetic number, because the mean of its divisors is an integer number (2064042).

Almost surely, 2^21223024 is an apocalyptic number.

It is an amenable number.

21223024 is a deficient number, since it is larger than the sum of its proper divisors (20057816).

21223024 is a wasteful number, since it uses less digits than its factorization.

21223024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5208 (or 5202 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21223024 is about 4606.8453414457. The cubic root of 21223024 is about 276.8656570724.

Adding to 21223024 its reverse (42032212), we get a palindrome (63255236).

The spelling of 21223024 in words is "twenty-one million, two hundred twenty-three thousand, twenty-four".