218841 has 16 divisors (see below), whose sum is σ = 353664. Its totient is φ = 117504.

The previous prime is 218839. The next prime is 218843. The reversal of 218841 is 148812.

Added to its reverse (148812) it gives a triangular number (367653 = T₈₅₇).

It is an interprime number because it is at equal distance from previous prime (218839) and next prime (218843).

It is not a de Polignac number, because 218841 - 2¹ = 218839 is a prime.

218841 is a lucky number.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (218843) 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 15 ways as a sum of consecutive naturals, for example, 51 + ... + 663.

It is an arithmetic number, because the mean of its divisors is an integer number (22104).

2²¹⁸⁸⁴¹ is an apocalyptic number.

218841 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

218841 is a deficient number, since it is larger than the sum of its proper divisors (134823).

218841 is a wasteful number, since it uses less digits than its factorization.

218841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 640.

The product of its digits is 512, while the sum is 24.

The square root of 218841 is about 467.8044463235. The cubic root of 218841 is about 60.2619106059.

Adding to 218841 its reverse (148812), we get a triangular number (367653 = T₈₅₇).

The spelling of 218841 in words is "two hundred eighteen thousand, eight hundred forty-one".