8891991988 has 12 divisors (see below), whose sum is σ = 16975621152. Its totient is φ = 4041814520.

The previous prime is 8891991971. The next prime is 8891991989.

8891991988 is nontrivially palindromic in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8891991989) 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 3 ways as a sum of consecutive naturals, for example, 101045320 + ... + 101045407.

It is an arithmetic number, because the mean of its divisors is an integer number (1414635096).

Almost surely, 2^8891991988 is an apocalyptic number.

It is an amenable number.

8891991988 is a deficient number, since it is larger than the sum of its proper divisors (8083629164).

8891991988 is a wasteful number, since it uses less digits than its factorization.

8891991988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202090742 (or 202090740 counting only the distinct ones).

The product of its digits is 26873856, while the sum is 70.

The square root of 8891991988 is about 94297.3593903880. The cubic root of 8891991988 is about 2071.7293605185.

The spelling of 8891991988 in words is "eight billion, eight hundred ninety-one million, nine hundred ninety-one thousand, nine hundred eighty-eight".