Thirty nine

The thirty-nine (39) is the natural number that follows 38 and precedes 40.

Math

• It is a composite number, which has the following factors: 1, 3, and 13. As the sum of its factors is 17 ≤ 39, it is a defective number.
• Number odd.
• It is the sum of five consecutive cousins (3 + 5 + 7 + 11 + 13). It is also the sum of the first three powers of 3 (3 ¹ +3 ² +3 ³).
• 39 is the smallest natural number that has three partitions in three parts that give the same product when multiplied: {25, 8, 6}, {24, 10, 5}, {20, 15, 4}.
• It's a Perrin number.
• A semi-press number.
• It's a square-free number.
• The F26A graph is a symmetrical graph with 39 edges.
• Størmer number.

Chemistry

• 39 is the atomic number of itrium.

Astronomy

• Messier M39 object is an open cluster in the Cygnus constellation.
• Object of the New General Catalog NGC 39 is a spiral galaxy in the Andromeda constellation.
• (39) Laetitia is an asteroid that forms part of the asteroid belt.
• 39 Leonis is a binary star in Leo's constellation.