1681 = 1 + 23 + 4 × 56 × 7 + 89
1681 = 9 + 8 + 76 × 5 + 4 × 321
1681 = 0^7 + 1^8 − 2^9 − 3^6 + 4^5 + 5^0 + 6^4 + 7^1 + 8^3 + 9^2
1681 = 9^2 + 40^2
1681^2 = 720^2 + 1519^2
1681 divides 51^5 - 1.
a(n) = 2*n^2 - 1, n = 29
Semiprime (Product of 2 Primes)
Factors: 1, 41, 1681
Representations, Binary to Hexadecimal:
11010010001_2
2022021_3
122101_4
23211_5
11441_6
4621_7
3221_8
2267_9
1299_11
b81_12
9c4_13
881_14
771_15
691_16
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