18420000 has 120 divisors (see below), whose sum is σ = 60618096. Its totient is φ = 4896000.

The previous prime is 18419981. The next prime is 18420007. The reversal of 18420000 is 2481.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (18420007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 59847 + ... + 60153.

Almost surely, 2^18420000 is an apocalyptic number.

18420000 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 18420000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30309048).

18420000 is an abundant number, since it is smaller than the sum of its proper divisors (42198096).

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

18420000 is an equidigital number, since it uses as much as digits as its factorization.

18420000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 18420000 is about 4291.8527467750. The cubic root of 18420000 is about 264.0968423409.

Adding to 18420000 its reverse (2481), we get a palindrome (18422481).

The spelling of 18420000 in words is "eighteen million, four hundred twenty thousand".