61 is a Prime Number. Prime(18)
61 = 12 × 3 + 4 + 5 × 6 + 7 + 8 + 9
61 = 9 + 8 + 7 + (6 + 5 + 4 + 3) × 2 + 1
61 = 0^6 + 1^9 − 2^8 − 3^7 + 4^5 + 5^3 + 6^4 + 7^2 + 8^1 + 9^0
61 = 5^2 + 6^2
61 = (11(1+1) + 1)/(1 + 1)
= 2(2+2+2) − 2 − 2/2
= (3 + 3/3)3 − 3
= (44 + 4)/4 − 4
= 55 + 5 + 5/5
= 66 − 6 + 6/6
= 7 × 7 + (77 + 7)/7
= 8 × 8 + 8 − 88/8
= 9 × 9 − 99/9 − 9
\( 61^2 = 11^2 + 60^2 \)
Sexy Prime (Primes p such that p + 6 is also prime)
Prime of the form k^2 + k + 41
a(n) = n^2 written backwards (16 = 4x4)
Number of meaningful differential operations of the 4-th order on the space R^9.
Keith number or Repfigit (Repetitive Fibonacci-like digit)
Factors: 1, 61
Sixty-one
Representations, Binary to Hexadecimal:
111101_2
2021_3
331_4
221_5
141_6
115_7
75_8
67_9
56_11
51_12
49_13
45_14
41_15
3d_16
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