20186818 has 8 divisors (see below), whose sum is σ = 30483900. Its totient is φ = 10025520.

The previous prime is 20186809. The next prime is 20186819. The reversal of 20186818 is 81868102.

It can be written as a sum of positive squares in 2 ways, for example, as 19686969 + 499849 = 4437^2 + 707^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20186819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33573 + ... + 34168.

Almost surely, 2^20186818 is an apocalyptic number.

20186818 is a deficient number, since it is larger than the sum of its proper divisors (10297082).

20186818 is a wasteful number, since it uses less digits than its factorization.

20186818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67892.

The product of its (nonzero) digits is 6144, while the sum is 34.

The square root of 20186818 is about 4492.9742932717. The cubic root of 20186818 is about 272.2843137985.

It can be divided in two parts, 2018 and 6818, that added together give a square (8836 = 94²).

The spelling of 20186818 in words is "twenty million, one hundred eighty-six thousand, eight hundred eighteen".