1986766866 has 80 divisors (see below), whose sum is σ = 5097495744. Its totient is φ = 566567136.

The previous prime is 1986766861. The next prime is 1986766949. The reversal of 1986766866 is 6686676891.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (1986766861) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 739161 + ... + 741843.

Almost surely, 2^1986766866 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1986766866, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2548747872).

1986766866 is an abundant number, since it is smaller than the sum of its proper divisors (3110728878).

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

1986766866 is a wasteful number, since it uses less digits than its factorization.

1986766866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3357 (or 3348 counting only the distinct ones).

The product of its digits is 31352832, while the sum is 63.

The square root of 1986766866 is about 44573.1630692730. The cubic root of 1986766866 is about 1257.1361145828.

The spelling of 1986766866 in words is "one billion, nine hundred eighty-six million, seven hundred sixty-six thousand, eight hundred sixty-six".