108807991 has 2 divisors, whose sum is σ = 108807992. Its totient is φ = 108807990.

The previous prime is 108807989. The next prime is 108808001. The reversal of 108807991 is 199708801.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 108807991 - 2¹ = 108807989 is a prime.

Together with 108807989, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (108807901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54403995 + 54403996.

It is an arithmetic number, because the mean of its divisors is an integer number (54403996).

Almost surely, 2^108807991 is an apocalyptic number.

108807991 is a deficient number, since it is larger than the sum of its proper divisors (1).

108807991 is an equidigital number, since it uses as much as digits as its factorization.

108807991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 108807991 is about 10431.1068923677. The cubic root of 108807991 is about 477.4049641370.

The spelling of 108807991 in words is "one hundred eight million, eight hundred seven thousand, nine hundred ninety-one".