168196993 has 2 divisors, whose sum is σ = 168196994. Its totient is φ = 168196992.

The previous prime is 168196957. The next prime is 168197027. The reversal of 168196993 is 399691861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 137194369 + 31002624 = 11713^2 + 5568^2 .

It is a cyclic number.

It is not a de Polignac number, because 168196993 - 2⁹ = 168196481 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 168196993.

It is not a weakly prime, because it can be changed into another prime (168196393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84098496 + 84098497.

It is an arithmetic number, because the mean of its divisors is an integer number (84098497).

Almost surely, 2^168196993 is an apocalyptic number.

It is an amenable number.

168196993 is a deficient number, since it is larger than the sum of its proper divisors (1).

168196993 is an equidigital number, since it uses as much as digits as its factorization.

168196993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 52.

The square root of 168196993 is about 12969.0783404219. The cubic root of 168196993 is about 552.0004211735. Note that the first 3 decimals are identical.

The spelling of 168196993 in words is "one hundred sixty-eight million, one hundred ninety-six thousand, nine hundred ninety-three".