109005991 has 2 divisors, whose sum is σ = 109005992. Its totient is φ = 109005990.

The previous prime is 109005977. The next prime is 109006049. The reversal of 109005991 is 199500901.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 109005991 - 2¹¹ = 109003943 is a prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (109005971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 54502995 + 54502996.

It is an arithmetic number, because the mean of its divisors is an integer number (54502996).

Almost surely, 2^109005991 is an apocalyptic number.

109005991 is a deficient number, since it is larger than the sum of its proper divisors (1).

109005991 is an equidigital number, since it uses as much as digits as its factorization.

109005991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3645, while the sum is 34.

The square root of 109005991 is about 10440.5934218319. The cubic root of 109005991 is about 477.6943696696.

It can be divided in two parts, 10 and 9005991, that added together give a square (9006001 = 3001²).

The spelling of 109005991 in words is "one hundred nine million, five thousand, nine hundred ninety-one".