18432220 has 12 divisors (see below), whose sum is σ = 38707704. Its totient is φ = 7372880.

The previous prime is 18432217. The next prime is 18432241. The reversal of 18432220 is 2223481.

It is a junction number, because it is equal to n+sod(n) for n = 18432191 and 18432200.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 460786 + ... + 460825.

It is an arithmetic number, because the mean of its divisors is an integer number (3225642).

Almost surely, 2^18432220 is an apocalyptic number.

18432220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18432220 is an abundant number, since it is smaller than the sum of its proper divisors (20275484).

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

18432220 is a wasteful number, since it uses less digits than its factorization.

18432220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 921620 (or 921618 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 18432220 is about 4293.2761383354. The cubic root of 18432220 is about 264.1552308680.

The spelling of 18432220 in words is "eighteen million, four hundred thirty-two thousand, two hundred twenty".