168636881 has 12 divisors (see below), whose sum is σ = 196403760. Its totient is φ = 144373320.

The previous prime is 168636877. The next prime is 168636901. The reversal of 168636881 is 188636861.

It is not a de Polignac number, because 168636881 - 2² = 168636877 is a prime.

It is a super-2 number, since 2×168636881² = 56876795266816322, which contains 22 as substring.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (168636581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 55910 + ... + 58848.

It is an arithmetic number, because the mean of its divisors is an integer number (16366980).

Almost surely, 2^168636881 is an apocalyptic number.

It is an amenable number.

168636881 is a deficient number, since it is larger than the sum of its proper divisors (27766879).

168636881 is a wasteful number, since it uses less digits than its factorization.

168636881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4124 (or 4117 counting only the distinct ones).

The product of its digits is 331776, while the sum is 47.

The square root of 168636881 is about 12986.0263745304. The cubic root of 168636881 is about 552.4812204669.

The spelling of 168636881 in words is "one hundred sixty-eight million, six hundred thirty-six thousand, eight hundred eighty-one".