1381 is a Prime Number, Prime(221)
1381 = 12 × 34 + 56 × 7 + 8 + 9
1381 = 98 + 76 × 5 + 43 × 21
1381 = 0^7 + 1^8 + 2^6 − 3^9 + 4^3 + 5^2 + 6^1 + 7^5 + 8^4 + 9^0
1381 = 15^2 + 34^2
1381^2 = 931^2 + 1020^2
1381 divides 75^5 - 1.
Prime p such that (p+1)/2 is prime.
1381 is an irregular prime, since it divides the numerator of the Bernoulli number B266.
Factors: 1, 1381
One thousand, three hundred eighty-one
Representations, Binary to Hexadecimal:
10101100101_2
1220011_3
111211_4
21011_5
10221_6
4012_7
2545_8
1804_9
1046_11
971_12
823_13
709_14
621_15
565_16
<--- --->
Undergraduate Texts in Mathematics
Graduate Studies in Mathematics
