87 = 22 + 32 + 52 + 72
87 = 1 + 2 × 3 + 4 + 5 + 6 + 7 × 8 + 9
87 = 9 + 8 × 7 + 6 + 5 + 4 + 3 × 2 + 1
87 = 0^9 + 1^0 − 2^6 + 3^8 − 4^7 + 5^5 + 6^3 + 7^1 + 8^2 + 9^4
87 = 111 − (1 + 1) × (11 + 1)
= 2 × 2 × 22 − 2/2
= 3 + 3 + 3 × 33
= 44 + 44 − 4/4
= 55 + ((5 + 5)/5)5
= 6 + 6 − 66 + 6 × 66/6
= 77 + (77 − 7)/7
= 88 − 8/8
= 99 − (99 + 9)/9
Number k for which k!/9 + 1 is Prime, 87!/9 + 1 = 234195255375503079690400057633265510581087082006817356924774723468294901747510352675631491470712754833859385753600000000000000000001
Semiprime (Product of 2 Primes)
Factors: 1, 3, 29, 87
Representations, Binary to Hexadecimal:
1010111_2
10020_3
1113_4
322_5
223_6
153_7
127_8
106_9
7a_11
73_12
69_13
63_14
5c_15
57_16
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