21238432 has 24 divisors (see below), whose sum is σ = 42203700. Its totient is φ = 10520064.

The previous prime is 21238429. The next prime is 21238433. The reversal of 21238432 is 23483212.

It can be written as a sum of positive squares in 2 ways, for example, as 21196816 + 41616 = 4604^2 + 204^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21238397 and 21238406.

It is not an unprimeable number, because it can be changed into a prime (21238433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444 + ... + 6532.

Almost surely, 2^21238432 is an apocalyptic number.

It is an amenable number.

21238432 is a deficient number, since it is larger than the sum of its proper divisors (20965268).

21238432 is a wasteful number, since it uses less digits than its factorization.

21238432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6208 (or 6200 counting only the distinct ones).

The product of its digits is 2304, while the sum is 25.

The square root of 21238432 is about 4608.5173320711. The cubic root of 21238432 is about 276.9326427212.

It can be divided in two parts, 2123 and 8432, that multiplied together give a triangular number (17901136 = T₅₉₈₃).

The spelling of 21238432 in words is "twenty-one million, two hundred thirty-eight thousand, four hundred thirty-two".