16181868891 has 16 divisors (see below), whose sum is σ = 23290248960. Its totient is φ = 9963048480.

The previous prime is 16181868883. The next prime is 16181868929. The reversal of 16181868891 is 19886818161.

It is not a de Polignac number, because 16181868891 - 2³ = 16181868883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16181868821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4041445 + ... + 4045446.

It is an arithmetic number, because the mean of its divisors is an integer number (1455640560).

Almost surely, 2^16181868891 is an apocalyptic number.

16181868891 is a deficient number, since it is larger than the sum of its proper divisors (7108380069).

16181868891 is a wasteful number, since it uses less digits than its factorization.

16181868891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8086946.

The product of its digits is 1327104, while the sum is 57.

The spelling of 16181868891 in words is "sixteen billion, one hundred eighty-one million, eight hundred sixty-eight thousand, eight hundred ninety-one".