21024412 has 12 divisors (see below), whose sum is σ = 38729320. Its totient is φ = 9958896.

The previous prime is 21024407. The next prime is 21024413. The reversal of 21024412 is 21442012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21024413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138243 + ... + 138394.

Almost surely, 2^21024412 is an apocalyptic number.

It is an amenable number.

21024412 is a deficient number, since it is larger than the sum of its proper divisors (17704908).

21024412 is a wasteful number, since it uses less digits than its factorization.

21024412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276660 (or 276658 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 21024412 is about 4585.2384888902. The cubic root of 21024412 is about 275.9992823618. Note that the first 3 decimals are identical.

Adding to 21024412 its reverse (21442012), we get a palindrome (42466424).

The spelling of 21024412 in words is "twenty-one million, twenty-four thousand, four hundred twelve".