1666546686 has 96 divisors (see below), whose sum is σ = 4443828480. Its totient is φ = 440517888.

The previous prime is 1666546667. The next prime is 1666546697. The reversal of 1666546686 is 6866456661.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 119785 + ... + 132971.

It is an arithmetic number, because the mean of its divisors is an integer number (46289880).

Almost surely, 2^1666546686 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666546686, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2221914240).

1666546686 is an abundant number, since it is smaller than the sum of its proper divisors (2777281794).

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

1666546686 is a wasteful number, since it uses less digits than its factorization.

1666546686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13278 (or 13275 counting only the distinct ones).

The product of its digits is 7464960, while the sum is 54.

The square root of 1666546686 is about 40823.3595628777. The cubic root of 1666546686 is about 1185.6026502520.

The spelling of 1666546686 in words is "one billion, six hundred sixty-six million, five hundred forty-six thousand, six hundred eighty-six".