21434432 has 28 divisors (see below), whose sum is σ = 44775120. Its totient is φ = 10152576.

The previous prime is 21434429. The next prime is 21434437. The reversal of 21434432 is 23443412.

It is a junction number, because it is equal to n+sod(n) for n = 21434398 and 21434407.

It is not an unprimeable number, because it can be changed into a prime (21434437) 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, 7598 + ... + 10029.

Almost surely, 2^21434432 is an apocalyptic number.

It is an amenable number.

21434432 is an abundant number, since it is smaller than the sum of its proper divisors (23340688).

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

21434432 is a wasteful number, since it uses less digits than its factorization.

21434432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17658 (or 17648 counting only the distinct ones).

The product of its digits is 2304, while the sum is 23.

The square root of 21434432 is about 4629.7334696503. The cubic root of 21434432 is about 277.7819313631.

Adding to 21434432 its reverse (23443412), we get a palindrome (44877844).

The spelling of 21434432 in words is "twenty-one million, four hundred thirty-four thousand, four hundred thirty-two".