18208489 has 4 divisors (see below), whose sum is σ = 19609156. Its totient is φ = 16807824.

The previous prime is 18208471. The next prime is 18208493. The reversal of 18208489 is 98480281.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 7371225 + 10837264 = 2715^2 + 3292^2 .

It is a cyclic number.

It is not a de Polignac number, because 18208489 - 2¹³ = 18200297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18208409) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 700314 + ... + 700339.

It is an arithmetic number, because the mean of its divisors is an integer number (4902289).

Almost surely, 2^18208489 is an apocalyptic number.

It is an amenable number.

18208489 is a deficient number, since it is larger than the sum of its proper divisors (1400667).

18208489 is a wasteful number, since it uses less digits than its factorization.

18208489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1400666.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 18208489 is about 4267.1406116977. The cubic root of 18208489 is about 263.0821017172.

The spelling of 18208489 in words is "eighteen million, two hundred eight thousand, four hundred eighty-nine".