1666228686 has 8 divisors (see below), whose sum is σ = 3332457384. Its totient is φ = 555409560.

The previous prime is 1666228679. The next prime is 1666228691. The reversal of 1666228686 is 6868226661.

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

1666228686 is an admirable number.

It is a congruent number.

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, 138852385 + ... + 138852396.

It is an arithmetic number, because the mean of its divisors is an integer number (416557173).

Almost surely, 2^1666228686 is an apocalyptic number.

1666228686 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1666228686 is a wasteful number, since it uses less digits than its factorization.

1666228686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277704786.

The product of its digits is 1990656, while the sum is 51.

The square root of 1666228686 is about 40819.4645481785. The cubic root of 1666228686 is about 1185.5272356979.

The spelling of 1666228686 in words is "one billion, six hundred sixty-six million, two hundred twenty-eight thousand, six hundred eighty-six".