109168991 has 2 divisors, whose sum is σ = 109168992. Its totient is φ = 109168990.

The previous prime is 109168973. The next prime is 109169023. The reversal of 109168991 is 199861901.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 109168991 - 2²² = 104974687 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (109168901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54584495 + 54584496.

It is an arithmetic number, because the mean of its divisors is an integer number (54584496).

Almost surely, 2^109168991 is an apocalyptic number.

109168991 is a deficient number, since it is larger than the sum of its proper divisors (1).

109168991 is an equidigital number, since it uses as much as digits as its factorization.

109168991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 44.

The square root of 109168991 is about 10448.3965755517. The cubic root of 109168991 is about 477.9323547652.

The spelling of 109168991 in words is "one hundred nine million, one hundred sixty-eight thousand, nine hundred ninety-one".