218743809861 has 32 divisors (see below), whose sum is σ = 323534573568. Its totient is φ = 130841061120.

The previous prime is 218743809829. The next prime is 218743809863. The reversal of 218743809861 is 168908347812.

It is not a de Polignac number, because 218743809861 - 2⁵ = 218743809829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218743809863) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 926595 + ... + 1138448.

It is an arithmetic number, because the mean of its divisors is an integer number (10110455424).

Almost surely, 2^218743809861 is an apocalyptic number.

It is an amenable number.

218743809861 is a deficient number, since it is larger than the sum of its proper divisors (104790763707).

218743809861 is a wasteful number, since it uses less digits than its factorization.

218743809861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2065161.

The product of its (nonzero) digits is 4644864, while the sum is 57.

The spelling of 218743809861 in words is "two hundred eighteen billion, seven hundred forty-three million, eight hundred nine thousand, eight hundred sixty-one".