5221 = 12 + 34 + (567 + 8) × 9
5221 = 9 × 8 × (7 + 65) + 4 + 32 + 1
5221 = 0^7 + 1^8 + 2^9 + 3^6 + 4^5 + 5^1 + 6^2 + 7^4 + 8^3 + 9^0
a(n) = 4*n^2 - 7*n + 4, n = 39
a(n) = n^2 written backwards (1225 = 352)
Centered 12-gonal number, or centered dodecagonal number: number of the form 6*k*(k-1) + 1.
Semiprime (Product of 2 Primes)
Factors: 1, 23, 227, 5221
Five thousand, two hundred twenty-one
Representations, Binary to Hexadecimal:
1010001100101_2
21011101_3
1101211_4
131341_5
40101_6
21136_7
12145_8
7141_9
3a17_11
3031_12
24b8_13
1c8d_14
1831_15
1465_16
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Undergraduate Texts in Mathematics
Graduate Studies in Mathematics
