218165956 has 12 divisors (see below), whose sum is σ = 394955820. Its totient is φ = 105321440.

The previous prime is 218165953. The next prime is 218165977. The reversal of 218165956 is 659561812.

It can be written as a sum of positive squares in 2 ways, for example, as 64802500 + 153363456 = 8050^2 + 12384^2 .

It is not an unprimeable number, because it can be changed into a prime (218165953) 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 3 ways as a sum of consecutive naturals, for example, 940255 + ... + 940486.

It is an arithmetic number, because the mean of its divisors is an integer number (32912985).

Almost surely, 2^218165956 is an apocalyptic number.

It is an amenable number.

218165956 is a deficient number, since it is larger than the sum of its proper divisors (176789864).

218165956 is a wasteful number, since it uses less digits than its factorization.

218165956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1880774 (or 1880772 counting only the distinct ones).

The product of its digits is 129600, while the sum is 43.

The square root of 218165956 is about 14770.4419703677. The cubic root of 218165956 is about 601.9988484285.

It can be divided in two parts, 21816 and 5956, that added together give a palindrome (27772).

The spelling of 218165956 in words is "two hundred eighteen million, one hundred sixty-five thousand, nine hundred fifty-six".