18428220 has 72 divisors (see below), whose sum is σ = 57430464. Its totient is φ = 4779648.

The previous prime is 18428213. The next prime is 18428227. The reversal of 18428220 is 2282481.

18428220 is a `hidden beast` number, since 18 + 428 + 220 = 666.

It is an interprime number because it is at equal distance from previous prime (18428213) and next prime (18428227).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18428227) 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 23 ways as a sum of consecutive naturals, for example, 5277 + ... + 8043.

Almost surely, 2^18428220 is an apocalyptic number.

18428220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18428220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28715232).

18428220 is an abundant number, since it is smaller than the sum of its proper divisors (39002244).

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

18428220 is a wasteful number, since it uses less digits than its factorization.

18428220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2819 (or 2814 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 18428220 is about 4292.8102683440. The cubic root of 18428220 is about 264.1361212624.

The spelling of 18428220 in words is "eighteen million, four hundred twenty-eight thousand, two hundred twenty".