108991097 has 4 divisors (see below), whose sum is σ = 115402356. Its totient is φ = 102579840.

The previous prime is 108991067. The next prime is 108991121. The reversal of 108991097 is 790199801.

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

It can be written as a sum of positive squares in 2 ways, for example, as 77810041 + 31181056 = 8821^2 + 5584^2 .

It is a cyclic number.

It is not a de Polignac number, because 108991097 - 2⁶ = 108991033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (108991037) 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, 3205604 + ... + 3205637.

It is an arithmetic number, because the mean of its divisors is an integer number (28850589).

Almost surely, 2^108991097 is an apocalyptic number.

108991097 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

108991097 is a deficient number, since it is larger than the sum of its proper divisors (6411259).

108991097 is an equidigital number, since it uses as much as digits as its factorization.

108991097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6411258.

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 108991097 is about 10439.8801238328. The cubic root of 108991097 is about 477.6726121376.

The spelling of 108991097 in words is "one hundred eight million, nine hundred ninety-one thousand, ninety-seven".