168396491 has 2 divisors, whose sum is σ = 168396492. Its totient is φ = 168396490.

The previous prime is 168396467. The next prime is 168396497. The reversal of 168396491 is 194693861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 168396491 - 2¹⁰ = 168395467 is a prime.

It is a super-2 number, since 2×168396491² = 56714756362226162, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (168396497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84198245 + 84198246.

It is an arithmetic number, because the mean of its divisors is an integer number (84198246).

Almost surely, 2^168396491 is an apocalyptic number.

168396491 is a deficient number, since it is larger than the sum of its proper divisors (1).

168396491 is an equidigital number, since it uses as much as digits as its factorization.

168396491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 279936, while the sum is 47.

The square root of 168396491 is about 12976.7673555474. The cubic root of 168396491 is about 552.2185770153.

The spelling of 168396491 in words is "one hundred sixty-eight million, three hundred ninety-six thousand, four hundred ninety-one".