218206039905 has 24 divisors (see below), whose sum is σ = 432255774912. Its totient is φ = 99751332384.

The previous prime is 218206039879. The next prime is 218206039907. The reversal of 218206039905 is 509930602812.

218206039905 is a `hidden beast` number, since 2 + 18 + 20 + 603 + 9 + 9 + 0 + 5 = 666.

It is not a de Polignac number, because 218206039905 - 2²⁴ = 218189262689 is a prime.

It is a super-2 number, since 2×218206039905² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (218206039907) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 346358479 + ... + 346359108.

It is an arithmetic number, because the mean of its divisors is an integer number (18010657288).

Almost surely, 2^218206039905 is an apocalyptic number.

It is an amenable number.

218206039905 is a deficient number, since it is larger than the sum of its proper divisors (214049735007).

218206039905 is a wasteful number, since it uses less digits than its factorization.

218206039905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 692717605 (or 692717602 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 218206039905 in words is "two hundred eighteen billion, two hundred six million, thirty-nine thousand, nine hundred five".