218489 has 6 divisors (see below), whose sum is σ = 226926. Its totient is φ = 210240.

The previous prime is 218479. The next prime is 218509. The reversal of 218489 is 984812.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 6889 + 211600 = 83^2 + 460^2 .

It is not a de Polignac number, because 218489 - 2⁸ = 218233 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2957 + ... + 3029.

It is an arithmetic number, because the mean of its divisors is an integer number (37821).

218489 is a Friedman number, since it can be written as 41*(9+8*8)^2, using all its digits and the basic arithmetic operations.

2²¹⁸⁴⁸⁹ is an apocalyptic number.

It is an amenable number.

218489 is a deficient number, since it is larger than the sum of its proper divisors (8437).

218489 is an frugal number, since it uses more digits than its factorization.

218489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187 (or 114 counting only the distinct ones).

The product of its digits is 4608, while the sum is 32.

The square root of 218489 is about 467.4280693326. The cubic root of 218489 is about 60.2295833671.

It can be divided in two parts, 2184 and 89, that multiplied together give a triangular number (194376 = T₆₂₃).

The spelling of 218489 in words is "two hundred eighteen thousand, four hundred eighty-nine".