168159881 has 2 divisors, whose sum is σ = 168159882. Its totient is φ = 168159880.

The previous prime is 168159863. The next prime is 168159917. The reversal of 168159881 is 188951861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 84345856 + 83814025 = 9184^2 + 9155^2 .

It is a cyclic number.

It is not a de Polignac number, because 168159881 - 2¹⁴ = 168143497 is a prime.

It is a super-2 number, since 2×168159881² = 56555491155868322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (168159821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 84079940 + 84079941.

It is an arithmetic number, because the mean of its divisors is an integer number (84079941).

Almost surely, 2^168159881 is an apocalyptic number.

It is an amenable number.

168159881 is a deficient number, since it is larger than the sum of its proper divisors (1).

168159881 is an equidigital number, since it uses as much as digits as its factorization.

168159881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 47.

The square root of 168159881 is about 12967.6474736168. The cubic root of 168159881 is about 551.9598192852.

The spelling of 168159881 in words is "one hundred sixty-eight million, one hundred fifty-nine thousand, eight hundred eighty-one".