81197 has 2 divisors, whose sum is σ = 81198. Its totient is φ = 81196.

The previous prime is 81181. The next prime is 81199. The reversal of 81197 is 79118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72361 + 8836 = 269^2 + 94^2 .

It is a cyclic number.

It is not a de Polignac number, because 81197 - 2⁴ = 81181 is a prime.

Together with 81199, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 9.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40598 + 40599.

It is an arithmetic number, because the mean of its divisors is an integer number (40599).

2⁸¹¹⁹⁷ is an apocalyptic number.

It is an amenable number.

81197 is a deficient number, since it is larger than the sum of its proper divisors (1).

81197 is an equidigital number, since it uses as much as digits as its factorization.

81197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 504, while the sum is 26.

The square root of 81197 is about 284.9508729588. The cubic root of 81197 is about 43.3025356447.

The spelling of 81197 in words is "eighty-one thousand, one hundred ninety-seven".