8991117819 has 6 divisors (see below), whose sum is σ = 12987170196. Its totient is φ = 5994078540.

The previous prime is 8991117803. The next prime is 8991117827. The reversal of 8991117819 is 9187111998.

It is not a de Polignac number, because 8991117819 - 2⁴ = 8991117803 is a prime.

It is a super-2 number, since 2×8991117819² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (8991117899) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 499506537 + ... + 499506554.

It is an arithmetic number, because the mean of its divisors is an integer number (2164528366).

Almost surely, 2^8991117819 is an apocalyptic number.

8991117819 is a deficient number, since it is larger than the sum of its proper divisors (3996052377).

8991117819 is a wasteful number, since it uses less digits than its factorization.

8991117819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 999013097 (or 999013094 counting only the distinct ones).

The product of its digits is 326592, while the sum is 54.

The square root of 8991117819 is about 94821.5050450055. The cubic root of 8991117819 is about 2079.3993133377.

The spelling of 8991117819 in words is "eight billion, nine hundred ninety-one million, one hundred seventeen thousand, eight hundred nineteen".