218139 has 16 divisors (see below), whose sum is σ = 316800. Its totient is φ = 133056.

The previous prime is 218137. The next prime is 218143. The reversal of 218139 is 931812.

218139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 218139 - 2¹ = 218137 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 218139.

It is not an unprimeable number, because it can be changed into a prime (218131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2407 + ... + 2495.

It is an arithmetic number, because the mean of its divisors is an integer number (19800).

2²¹⁸¹³⁹ is an apocalyptic number.

218139 is a deficient number, since it is larger than the sum of its proper divisors (98661).

218139 is a wasteful number, since it uses less digits than its factorization.

218139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154.

The product of its digits is 432, while the sum is 24.

The square root of 218139 is about 467.0535301226. The cubic root of 218139 is about 60.1974053620.

The spelling of 218139 in words is "two hundred eighteen thousand, one hundred thirty-nine".