218111668 has 36 divisors (see below), whose sum is σ = 412644960. Its totient is φ = 100681504.

The previous prime is 218111657. The next prime is 218111669. The reversal of 218111668 is 866111812.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218111669) 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 11 ways as a sum of consecutive naturals, for example, 75963 + ... + 78781.

It is an arithmetic number, because the mean of its divisors is an integer number (11462360).

Almost surely, 2^218111668 is an apocalyptic number.

It is an amenable number.

218111668 is a deficient number, since it is larger than the sum of its proper divisors (194533292).

218111668 is a wasteful number, since it uses less digits than its factorization.

218111668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2904 (or 2873 counting only the distinct ones).

The product of its digits is 4608, while the sum is 34.

The square root of 218111668 is about 14768.6041317384. The cubic root of 218111668 is about 601.9489108714.

The spelling of 218111668 in words is "two hundred eighteen million, one hundred eleven thousand, six hundred sixty-eight".