18890000 has 50 divisors (see below), whose sum is σ = 45758790. Its totient is φ = 7552000.

The previous prime is 18889999. The next prime is 18890021. The reversal of 18890000 is 9881.

18890000 is nontrivially palindromic in base 7.

It can be written as a sum of positive squares in 5 ways, for example, as 7573504 + 11316496 = 2752^2 + 3364^2 .

It is a tau number, because it is divible by the number of its divisors (50).

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 9056 + ... + 10944.

Almost surely, 2^18890000 is an apocalyptic number.

18890000 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 18890000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22879395).

18890000 is an abundant number, since it is smaller than the sum of its proper divisors (26868790).

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

18890000 is an equidigital number, since it uses as much as digits as its factorization.

18890000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1917 (or 1896 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 18890000 is about 4346.2627624201. The cubic root of 18890000 is about 266.3242131871.

Adding to 18890000 its reverse (9881), we get a palindrome (18899881).

The spelling of 18890000 in words is "eighteen million, eight hundred ninety thousand".