186138866 has 8 divisors (see below), whose sum is σ = 279313920. Its totient is φ = 93034228.

The previous prime is 186138863. The next prime is 186138889. The reversal of 186138866 is 668831681.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a pancake number, because a pancake can be divided into 186138866 parts by 19294 straight cuts.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 186138866.

It is not an unprimeable number, because it can be changed into a prime (186138863) 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 3 ways as a sum of consecutive naturals, for example, 10406 + ... + 21921.

It is an arithmetic number, because the mean of its divisors is an integer number (34914240).

Almost surely, 2^186138866 is an apocalyptic number.

186138866 is a deficient number, since it is larger than the sum of its proper divisors (93175054).

186138866 is a wasteful number, since it uses less digits than its factorization.

186138866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35208.

The product of its digits is 331776, while the sum is 47.

The square root of 186138866 is about 13643.2718216709. The cubic root of 186138866 is about 570.9687701131.

The spelling of 186138866 in words is "one hundred eighty-six million, one hundred thirty-eight thousand, eight hundred sixty-six".