641

Sexy Prime (Primes p such that p + 6 is also prime)

641 = 1 × 234 + 5 × 67 + 8 × 9

641 = (9 + 87) × 6 + 5 × (4 + 3 × (2 + 1))

641 = 0^4 + 1^6 + 2^8 − 3^9 + 4^7 + 5^5 + 6^2 + 7^0 + 8^3 + 9^1

641 = 4^2 + 25^2

641 = 2^4 + 5^4

641^2 = 200^2 + 609^2

641 divides 79^10 - 1.

Number of conjugacy classes in the alternating group A_23.

Quartan prime: primes of the form x^4 + y^4, × > 0, y > 0.

Sophie Germain prime p (List): 2p+1 is also prime (1283)

Number that is the sum of 6 positive 7th powers.

Factors: 1, 641

Representations, Binary to Hexadecimal:

1010000001_2
212202_3
22001_4
10031_5
2545_6
1604_7
1201_8
782_9
533_11
455_12
3a4_13
33b_14
2cb_15
281_16

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