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21193 is a prime number
BaseRepresentation
bin101001011001001
31002001221
411023021
51134233
6242041
7115534
oct51311
932057
1021193
1114a17
1210321
139853
147a1b
15642d
hex52c9

21193 has 2 divisors, whose sum is σ = 21194. Its totient is φ = 21192.

The previous prime is 21191. The next prime is 21211. The reversal of 21193 is 39112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12544 + 8649 = 112^2 + 93^2 .

It is a cyclic number.

It is not a de Polignac number, because 21193 - 21 = 21191 is a prime.

Together with 21191, it forms a pair of twin primes.

It is an Ulam number.

21193 is a lucky number.

It is a nialpdrome in base 13.

It is not a weakly prime, because it can be changed into another prime (21191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10596 + 10597.

It is an arithmetic number, because the mean of its divisors is an integer number (10597).

221193 is an apocalyptic number.

It is an amenable number.

21193 is a deficient number, since it is larger than the sum of its proper divisors (1).

21193 is an equidigital number, since it uses as much as digits as its factorization.

21193 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54, while the sum is 16.

The square root of 21193 is about 145.5781577023. The cubic root of 21193 is about 27.6735035764.

The spelling of 21193 in words is "twenty-one thousand, one hundred ninety-three".