511 (number)

511 is the natural number following 510 and preceding 512.

 ← 510 511 512 →
Cardinalfive hundred eleven
Ordinal511th
(five hundred eleventh)
Factorization7 × 73
Greek numeralΦΙΑ´
Roman numeralDXI
Binary1111111112
Ternary2002213
Senary22116
Octal7778
Duodecimal36712
It is a Mersenne number, being one less than a power of 2: ${\displaystyle 511=2^{9}-1}$. As a result, 511 is a palindromic number and a repdigit in bases 2 (1111111112). It is also palindromic and a repdigit in base 8 (7778).
It is a generalized heptagonal number (sequence A085787 in the OEIS), since ${\displaystyle 511={\frac {1}{2}}(5n^{2}-3n)}$ when ${\displaystyle n=-14}$.