168891197 has 2 divisors, whose sum is σ = 168891198. Its totient is φ = 168891196.

The previous prime is 168891187. The next prime is 168891211. The reversal of 168891197 is 791198861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 140043556 + 28847641 = 11834^2 + 5371^2 .

It is a cyclic number.

It is not a de Polignac number, because 168891197 - 2⁴ = 168891181 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (168891137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84445598 + 84445599.

It is an arithmetic number, because the mean of its divisors is an integer number (84445599).

Almost surely, 2^168891197 is an apocalyptic number.

It is an amenable number.

168891197 is a deficient number, since it is larger than the sum of its proper divisors (1).

168891197 is an equidigital number, since it uses as much as digits as its factorization.

168891197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 50.

The square root of 168891197 is about 12995.8145954765. The cubic root of 168891197 is about 552.7588075168.

The spelling of 168891197 in words is "one hundred sixty-eight million, eight hundred ninety-one thousand, one hundred ninety-seven".