8191988 has 24 divisors (see below), whose sum is σ = 16454592. Its totient is φ = 3495744.

The previous prime is 8191969. The next prime is 8191991. The reversal of 8191988 is 8891918.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8120 + ... + 9072.

It is an arithmetic number, because the mean of its divisors is an integer number (685608).

Almost surely, 2^8191988 is an apocalyptic number.

It is an amenable number.

8191988 is an abundant number, since it is smaller than the sum of its proper divisors (8262604).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8191988 is a wasteful number, since it uses less digits than its factorization.

8191988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1271 (or 1269 counting only the distinct ones).

The product of its digits is 41472, while the sum is 44.

The square root of 8191988 is about 2862.1649148852. The cubic root of 8191988 is about 201.5872695518.

The spelling of 8191988 in words is "eight million, one hundred ninety-one thousand, nine hundred eighty-eight".