861818668236 has 18 divisors (see below), whose sum is σ = 2178486078132. Its totient is φ = 287272889400.

The previous prime is 861818668153. The next prime is 861818668253. The reversal of 861818668236 is 632866818168.

861818668236 is a `hidden beast` number, since 8 + 618 + 1 + 8 + 6 + 6 + 8 + 2 + 3 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11969703690 + ... + 11969703761.

Almost surely, 2^861818668236 is an apocalyptic number.

It is an amenable number.

861818668236 is an abundant number, since it is smaller than the sum of its proper divisors (1316667409896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861818668236 is a wasteful number, since it uses less digits than its factorization.

861818668236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23939407461 (or 23939407456 counting only the distinct ones).

The product of its digits is 31850496, while the sum is 63.

The spelling of 861818668236 in words is "eight hundred sixty-one billion, eight hundred eighteen million, six hundred sixty-eight thousand, two hundred thirty-six".