218134865 has 16 divisors (see below), whose sum is σ = 283470096. Its totient is φ = 160185600.

The previous prime is 218134843. The next prime is 218134907. The reversal of 218134865 is 568431812.

It can be written as a sum of positive squares in 8 ways, for example, as 73942801 + 144192064 = 8599^2 + 12008^2 .

It is not a de Polignac number, because 218134865 - 2¹² = 218130769 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is an unprimeable number.

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, 2495 + ... + 21035.

It is an arithmetic number, because the mean of its divisors is an integer number (17716881).

Almost surely, 2^218134865 is an apocalyptic number.

It is an amenable number.

218134865 is a deficient number, since it is larger than the sum of its proper divisors (65335231).

218134865 is a wasteful number, since it uses less digits than its factorization.

218134865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18740.

The product of its digits is 46080, while the sum is 38.

The square root of 218134865 is about 14769.3894592837. The cubic root of 218134865 is about 601.9702499619.

The spelling of 218134865 in words is "two hundred eighteen million, one hundred thirty-four thousand, eight hundred sixty-five".