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BaseRepresentation
bin110000101
3112102
412011
53024
61445
71064
oct605
9472
10389
11324
12285
1323c
141db
151ae
hex185

389 has 2 divisors, whose sum is σ = 390. Its totient is φ = 388.

The previous prime is 383. The next prime is 397. The reversal of 389 is 983.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 289 + 100 = 17^2 + 10^2 .

It is an emirp because it is prime and its reverse (983) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 389 - 24 = 373 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a plaindrome in base 6, base 10, base 13 and base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 389.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 194 + 195.

It is an arithmetic number, because the mean of its divisors is an integer number (195).

It is an amenable number.

389 is a deficient number, since it is larger than the sum of its proper divisors (1).

389 is an equidigital number, since it uses as much as digits as its factorization.

389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 216, while the sum is 20.

The square root of 389 is about 19.7230829233. The cubic root of 389 is about 7.2998936621.

The spelling of 389 in words is "three hundred eighty-nine", and thus it is an aban number and an oban number.