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1986 = 23331

1986 has 8 divisors (see below), whose sum is σ = 3984. Its totient is φ = 660.

The previous prime is 1979. The next prime is 1987. The reversal of 1986 is 6891.

1986 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

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

1986 is an admirable number.

1986 is strictly pandigital in base 5.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 1986.

It is not an unprimeable number, because it can be changed into a prime (1987) by changing a digit.

1986 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 160 + ... + 171.

It is an arithmetic number, because the mean of its divisors is an integer number (498).

1986 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.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1992).

1986 is a wasteful number, since it uses less digits than its factorization.

1986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336.

The product of its digits is 432, while the sum is 24.

The square root of 1986 is about 44.5645599103. The cubic root of 1986 is about 12.5697434774.

It can be divided in two parts, 19 and 86, that added together give a triangular number (105 = T14).

The spelling of 1986 in words is "one thousand, nine hundred eighty-six".

Divisors: 1 2 3 6 331 662 993 1986