421 is a Prime Number, Prime(82)
421 = 1 + 2 × 34 + 5 × 67 + 8 + 9
421 = 9 + 8 + 76 × 5 + 4 × 3 × 2 × 1
421 = 14^2 + 15^2
421^2 = 29^2 + 420^2
421 = 2^9 - 91
Prime of the form k^2 + k + 41
Prime of the form x^2 + xy + 2y^2, with × and y nonnegative
Prime p such that (p+1)/2 is prime.
Odd number n such that 3^n+1 is a sum of two squares.
Prime of the form 1 + n + n^2 + n^3 + ... + n^k, n > 1, k > 1, n = 11
Factors: 1, 421
Four hundred twenty-one
Roman: CDXXI
Representations, Binary to Hexadecimal:
110100101_2
120121_3
12211_4
3141_5
1541_6
1141_7
645_8
517_9
353_11
2b1_12
265_13
221_14
1d1_15
1a5_16
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