218161611 has 12 divisors (see below), whose sum is σ = 315770520. Its totient is φ = 145141920.

The previous prime is 218161609. The next prime is 218161627. The reversal of 218161611 is 116161812.

It is not a de Polignac number, because 218161611 - 2¹ = 218161609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (218161711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20266 + ... + 29103.

It is an arithmetic number, because the mean of its divisors is an integer number (26314210).

Almost surely, 2^218161611 is an apocalyptic number.

218161611 is a deficient number, since it is larger than the sum of its proper divisors (97608909).

218161611 is a wasteful number, since it uses less digits than its factorization.

218161611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49866 (or 49863 counting only the distinct ones).

The product of its digits is 576, while the sum is 27.

The square root of 218161611 is about 14770.2948853434. The cubic root of 218161611 is about 601.9948519260.

The spelling of 218161611 in words is "two hundred eighteen million, one hundred sixty-one thousand, six hundred eleven".