21432318 has 16 divisors (see below), whose sum is σ = 43862016. Its totient is φ = 6977880.

The previous prime is 21432317. The next prime is 21432331. The reversal of 21432318 is 81323412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41278 + ... + 41793.

It is an arithmetic number, because the mean of its divisors is an integer number (2741376).

Almost surely, 2^21432318 is an apocalyptic number.

21432318 is an abundant number, since it is smaller than the sum of its proper divisors (22429698).

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

21432318 is a wasteful number, since it uses less digits than its factorization.

21432318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83119.

The product of its digits is 1152, while the sum is 24.

The square root of 21432318 is about 4629.5051571415. The cubic root of 21432318 is about 277.7727988559.

The spelling of 21432318 in words is "twenty-one million, four hundred thirty-two thousand, three hundred eighteen".