18428940 has 72 divisors (see below), whose sum is σ = 57225168. Its totient is φ = 4798080.

The previous prime is 18428929. The next prime is 18428941. The reversal of 18428940 is 4982481.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18428895 and 18428904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18428941) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6550 + ... + 8930.

It is an arithmetic number, because the mean of its divisors is an integer number (794794).

Almost surely, 2^18428940 is an apocalyptic number.

18428940 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 18428940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28612584).

18428940 is an abundant number, since it is smaller than the sum of its proper divisors (38796228).

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

18428940 is a wasteful number, since it uses less digits than its factorization.

18428940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2439 (or 2434 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 18428940 is about 4292.8941286736. The cubic root of 18428940 is about 264.1395611955.

The spelling of 18428940 in words is "eighteen million, four hundred twenty-eight thousand, nine hundred forty".