18418500 has 72 divisors (see below), whose sum is σ = 58118424. Its totient is φ = 4910400.

The previous prime is 18418487. The next prime is 18418537. The reversal of 18418500 is 581481.

It can be written as a sum of positive squares in 4 ways, for example, as 1179396 + 17239104 = 1086^2 + 4152^2 .

It is a super-2 number, since 2×18418500² = 678482284500000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2454 + ... + 6546.

Almost surely, 2^18418500 is an apocalyptic number.

18418500 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 18418500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29059212).

18418500 is an abundant number, since it is smaller than the sum of its proper divisors (39699924).

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

18418500 is a wasteful number, since it uses less digits than its factorization.

18418500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4118 (or 4103 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 18418500 is about 4291.6779935126. The cubic root of 18418500 is about 264.0896733938.

Adding to 18418500 its reverse (581481), we get a palindrome (18999981).

The spelling of 18418500 in words is "eighteen million, four hundred eighteen thousand, five hundred".