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197 is a prime number

197 has 2 divisors, whose sum is σ = 198. Its totient is φ = 196.

The previous prime is 193. The next prime is 199. The reversal of 197 is 791.

197 is nontrivially palindromic in base 6 and base 14.

197 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Cunningham number, because it is equal to 142+1.

197 is an esthetic number in base 14, because in such base its adjacent digits differ by 1.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196 + 1 = 14^2 + 1^2 .

197 is a truncatable prime.

It is a cyclic number.

It is not a de Polignac number, because 197 - 22 = 193 is a prime.

Together with 199, it forms a pair of twin primes.

It is a Chen prime.

197 is a repfigit number.

It is an Ulam number.

197 is an undulating number in base 6 and base 14.

It is a plaindrome in base 9, base 11, base 12 and base 13.

It is a nialpdrome in base 15 and base 16.

It is a congruent number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98 + 99.

It is an arithmetic number, because the mean of its divisors is an integer number (99).

197 is the 8-th centered heptagonal number.

It is an amenable number.

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

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

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

The product of its digits is 63, while the sum is 17.

The square root of 197 is about 14.0356688476. The cubic root of 197 is about 5.8186478675.

The spelling of 197 in words is "one hundred ninety-seven", and thus it is an aban number.