163887891 has 4 divisors (see below), whose sum is σ = 218517192. Its totient is φ = 109258592.

The previous prime is 163887883. The next prime is 163887923. The reversal of 163887891 is 198788361.

163887891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 163887891 - 2³ = 163887883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (163887851) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27314646 + ... + 27314651.

It is an arithmetic number, because the mean of its divisors is an integer number (54629298).

Almost surely, 2^163887891 is an apocalyptic number.

163887891 is a deficient number, since it is larger than the sum of its proper divisors (54629301).

163887891 is an equidigital number, since it uses as much as digits as its factorization.

163887891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54629300.

The product of its digits is 580608, while the sum is 51.

The square root of 163887891 is about 12801.8706055014. The cubic root of 163887891 is about 547.2456131450.

The spelling of 163887891 in words is "one hundred sixty-three million, eight hundred eighty-seven thousand, eight hundred ninety-one".