21425232 has 40 divisors (see below), whose sum is σ = 56532096. Its totient is φ = 6989056.

The previous prime is 21425227. The next prime is 21425233. The reversal of 21425232 is 23252412.

It is a junction number, because it is equal to n+sod(n) for n = 21425199 and 21425208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21425233) 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 7 ways as a sum of consecutive naturals, for example, 2493 + ... + 7004.

Almost surely, 2^21425232 is an apocalyptic number.

It is an amenable number.

21425232 is an abundant number, since it is smaller than the sum of its proper divisors (35106864).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21425232 is a wasteful number, since it uses less digits than its factorization.

21425232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9555 (or 9549 counting only the distinct ones).

The product of its digits is 960, while the sum is 21.

The square root of 21425232 is about 4628.7397852979. The cubic root of 21425232 is about 277.7421828642.

Adding to 21425232 its reverse (23252412), we get a palindrome (44677644).

The spelling of 21425232 in words is "twenty-one million, four hundred twenty-five thousand, two hundred thirty-two".