18992389 has 12 divisors (see below), whose sum is σ = 21075012. Its totient is φ = 17097600.

The previous prime is 18992377. The next prime is 18992401. The reversal of 18992389 is 98329981.

It is an interprime number because it is at equal distance from previous prime (18992377) and next prime (18992401).

It can be written as a sum of positive squares in 6 ways, for example, as 9351364 + 9641025 = 3058^2 + 3105^2 .

It is not a de Polignac number, because 18992389 - 2⁵ = 18992357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18992329) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5559 + ... + 8299.

It is an arithmetic number, because the mean of its divisors is an integer number (1756251).

Almost surely, 2^18992389 is an apocalyptic number.

It is an amenable number.

18992389 is a deficient number, since it is larger than the sum of its proper divisors (2082623).

18992389 is a wasteful number, since it uses less digits than its factorization.

18992389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2808 (or 2795 counting only the distinct ones).

The product of its digits is 279936, while the sum is 49.

The square root of 18992389 is about 4358.0258145174. The cubic root of 18992389 is about 266.8045299294.

The spelling of 18992389 in words is "eighteen million, nine hundred ninety-two thousand, three hundred eighty-nine".