85665197 has 2 divisors, whose sum is σ = 85665198. Its totient is φ = 85665196.

The previous prime is 85665127. The next prime is 85665199. The reversal of 85665197 is 79156658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85119076 + 546121 = 9226^2 + 739^2 .

It is a cyclic number.

It is not a de Polignac number, because 85665197 - 2²⁴ = 68887981 is a prime.

Together with 85665199, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (85665199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42832598 + 42832599.

It is an arithmetic number, because the mean of its divisors is an integer number (42832599).

Almost surely, 2^85665197 is an apocalyptic number.

It is an amenable number.

85665197 is a deficient number, since it is larger than the sum of its proper divisors (1).

85665197 is an equidigital number, since it uses as much as digits as its factorization.

85665197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 47.

The square root of 85665197 is about 9255.5495244745. The cubic root of 85665197 is about 440.8269520539.

The spelling of 85665197 in words is "eighty-five million, six hundred sixty-five thousand, one hundred ninety-seven".