168888891 has 8 divisors (see below), whose sum is σ = 237037120. Its totient is φ = 106666632.

The previous prime is 168888883. The next prime is 168888893. The reversal of 168888891 is 198888861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 168888891 - 2³ = 168888883 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 2962963 = 168888891 / (1 + 6 + 8 + 8 + 8 + 8 + 8 + 9 + 1).

168888891 is a strobogrammatic number because it is the same when read upside-down.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (168888893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1481425 + ... + 1481538.

It is an arithmetic number, because the mean of its divisors is an integer number (29629640).

Almost surely, 2^168888891 is an apocalyptic number.

168888891 is a deficient number, since it is larger than the sum of its proper divisors (68148229).

168888891 is a wasteful number, since it uses less digits than its factorization.

168888891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2962985.

The product of its digits is 1769472, while the sum is 57.

The square root of 168888891 is about 12995.7258743019. The cubic root of 168888891 is about 552.7562917598.

The spelling of 168888891 in words is "one hundred sixty-eight million, eight hundred eighty-eight thousand, eight hundred ninety-one".