218513 has 2 divisors, whose sum is σ = 218514. Its totient is φ = 218512.

The previous prime is 218509. The next prime is 218521. The reversal of 218513 is 315812.

218513 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146689 + 71824 = 383^2 + 268^2 .

It is a cyclic number.

It is not a de Polignac number, because 218513 - 2² = 218509 is a prime.

It is a nialpdrome in base 12.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 218513.

It is not a weakly prime, because it can be changed into another prime (218213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109256 + 109257.

It is an arithmetic number, because the mean of its divisors is an integer number (109257).

2²¹⁸⁵¹³ is an apocalyptic number.

It is an amenable number.

218513 is a deficient number, since it is larger than the sum of its proper divisors (1).

218513 is an equidigital number, since it uses as much as digits as its factorization.

218513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 240, while the sum is 20.

The square root of 218513 is about 467.4537410269. The cubic root of 218513 is about 60.2317885995.

The spelling of 218513 in words is "two hundred eighteen thousand, five hundred thirteen".