1987 (number)

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1986 1987 1988
Cardinal one thousand nine hundred eighty-seven
Ordinal 1987th
(one thousand nine hundred and eighty-seventh)
Factorization 1987
Prime yes
Roman numeral MCMLXXXVII
Binary 111110000112
Ternary 22011213
Quaternary 1330034
Quinary 304225
Senary 131116
Octal 37038
Duodecimal 119712
Hexadecimal 7C316
Vigesimal 4J720
Base 36 1J736

1987 is the natural number following 1986 and preceding 1988.

In mathematics[edit]

1987 is an odd number and the 300th prime number. It starts the 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[edit]

References[edit]

  1. ^ (sequence A075223 in OEIS).
  2. ^ National Oceanic and Atmospheric Administration, "Chemical data sheet for: ALCOHOLS, N.O.S.".
  3. ^ (sequence A061997 in OEIS).