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1983 = 3661

1983 has 4 divisors (see below), whose sum is σ = 2648. Its totient is φ = 1320.

The previous prime is 1979. The next prime is 1987. The reversal of 1983 is 3891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3891 = 31297.

It is an interprime number because it is at equal distance from previous prime (1979) and next prime (1987).

It is not a de Polignac number, because 1983 - 22 = 1979 is a prime.

It is a D-number.

It is a Duffinian number.

It is the 27-th Perrin number.

1983 is a lucky number.

It is a plaindrome in base 8 and base 16.

It is a nialpdrome in base 7 and base 13.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 1983.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 328 + ... + 333.

It is an arithmetic number, because the mean of its divisors is an integer number (662).

1983 is a deficient number, since it is larger than the sum of its proper divisors (665).

1983 is an equidigital number, since it uses as much as digits as its factorization.

1983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 664.

The product of its digits is 216, while the sum is 21.

The square root of 1983 is about 44.5308881564. The cubic root of 1983 is about 12.5634111119.

The spelling of 1983 in words is "one thousand, nine hundred eighty-three".

Divisors: 1 3 661 1983