1,771,561

Number

$1 \, 771 \, 561$ (one million, seven hundred and seventy-one thousand, five hundred and sixty-one) is:

$11^6$

The $4$th, and highest known, odd number after $1$, $5$, $1549$ which cannot be expressed as the sum of an integer power and a prime number

The $6$th power of $11$ after $(1)$, $11$, $121$, $1331$, $14 \, 641$, $161 \, 051$:

$1 \, 771 \, 561 = 11^6$

The $11$th sixth power after $1$, $64$, $729$, $4096$, $15 \, 625$, $46 \, 656$, $117 \, 649$, $262 \, 144$, $531 \, 441$, $1 \, 000 \, 000$:

$1 \, 771 \, 561 = 11 \times 11 \times 11 \times 11 \times 11 \times 11$

The $121$st cube number:

$1 \, 771 \, 561 = 121 \times 121 \times 121$

The $1331$st square number:

$1 \, 771 \, 561 = 1331 \times 1331$