66218818 has 8 divisors (see below), whose sum is σ = 99420048. Its totient is φ = 33078804.

The previous prime is 66218809. The next prime is 66218849. The reversal of 66218818 is 81881266.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12496 + ... + 16987.

It is an arithmetic number, because the mean of its divisors is an integer number (12427506).

Almost surely, 2^66218818 is an apocalyptic number.

66218818 is a deficient number, since it is larger than the sum of its proper divisors (33201230).

66218818 is a wasteful number, since it uses less digits than its factorization.

66218818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30608.

The product of its digits is 36864, while the sum is 40.

The square root of 66218818 is about 8137.4945775712. The cubic root of 66218818 is about 404.5701235686.

The spelling of 66218818 in words is "sixty-six million, two hundred eighteen thousand, eight hundred eighteen".