31 (number)

natural number
(Redirected from Thirty-one)

31 (thirty-one) is a number. It comes between thirty and thirty-two, and is an odd number. It is also the 11th prime number, after 2, 3, 5, 7, 11, 13, 17, 19, 23, and 29.

← 30 31 32 →
Cardinalthirty-one
Ordinal31st
(thirty-first)
Factorizationprime
Greek numeralΛΑ´
Roman numeralXXXI
Binary111112
Ternary10113
Quaternary1334
Quinary1115
Senary516
Octal378
Duodecimal2712
Hexadecimal1F16
Vigesimal1B20
Base 36V36

The factors of thirty-one are 1 and 31.

In Roman Numerals, 31 is written as XXXI.