21432284 has 24 divisors (see below), whose sum is σ = 38911488. Its totient is φ = 10318320.

The previous prime is 21432283. The next prime is 21432293. The reversal of 21432284 is 48223412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37787 + ... + 38349.

It is an arithmetic number, because the mean of its divisors is an integer number (1621312).

Almost surely, 2^21432284 is an apocalyptic number.

It is an amenable number.

21432284 is a deficient number, since it is larger than the sum of its proper divisors (17479204).

21432284 is a wasteful number, since it uses less digits than its factorization.

21432284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 905 (or 903 counting only the distinct ones).

The product of its digits is 3072, while the sum is 26.

The square root of 21432284 is about 4629.5014850413. The cubic root of 21432284 is about 277.7726519706.

Adding to 21432284 its reverse (48223412), we get a palindrome (69655696).

The spelling of 21432284 in words is "twenty-one million, four hundred thirty-two thousand, two hundred eighty-four".