18801889 has 4 divisors (see below), whose sum is σ = 19450260. Its totient is φ = 18153520.

The previous prime is 18801869. The next prime is 18801899. The reversal of 18801889 is 98810881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98810881 = 13 ⋅7600837.

It can be written as a sum of positive squares in 2 ways, for example, as 5841889 + 12960000 = 2417^2 + 3600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18801889 is a prime.

It is a super-2 number, since 2×18801889² = 707022059936642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18801859) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324142 + ... + 324199.

It is an arithmetic number, because the mean of its divisors is an integer number (4862565).

Almost surely, 2^18801889 is an apocalyptic number.

It is an amenable number.

18801889 is a deficient number, since it is larger than the sum of its proper divisors (648371).

18801889 is an equidigital number, since it uses as much as digits as its factorization.

18801889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648370.

The product of its (nonzero) digits is 36864, while the sum is 43.

The square root of 18801889 is about 4336.1145049456. The cubic root of 18801889 is about 265.9094845322.

The spelling of 18801889 in words is "eighteen million, eight hundred one thousand, eight hundred eighty-nine".