1987 (number)

← 1986 1987 1988 →
List of numbers Integers ← 0 1k 2k 3k 4k 5k 6k 7k 8k 9k →
Cardinal	one thousand nine hundred eighty-seven
Ordinal	1987th (one thousand nine hundred eighty-seventh)
Factorization	prime
Prime	300th
Greek numeral	,ΑϠΠΖ´
Roman numeral	MCMLXXXVII, mcmlxxxvii
Binary	111110000112
Ternary	22011213
Senary	131116
Octal	37038
Duodecimal	119712
Hexadecimal	7C316

1987 is the natural number following 1986 and preceding 1988.

In mathematics

1987 is an odd number and the 300th prime number. It is the first number of a sexy prime triplet (1987, 1993, 1999). Being of the form 4n + 3, it is a Gaussian prime. It is a lucky number and therefore also a lucky prime. 1987 is a prime factor of the 9th number in Sylvester's sequence, and is the 15th prime to divide any number in the sequence.

There are 1987 polyiamonds with 12 cells that tile the plane isohedrally. ^[1]

In other fields

• There are 1987 ways to place four non-attacking chess kings on a 5 × 5 board. ^[2]

References

1. (sequence A075223 in the OEIS ).
2. (sequence A061997 in the OEIS ).