27891109 has 2 divisors, whose sum is σ = 27891110. Its totient is φ = 27891108.

The previous prime is 27891077. The next prime is 27891119. The reversal of 27891109 is 90119872.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15038884 + 12852225 = 3878^2 + 3585^2 .

It is a cyclic number.

It is not a de Polignac number, because 27891109 - 2⁵ = 27891077 is a prime.

It is a super-2 number, since 2×27891109² = 1555827922499762, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27891119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13945554 + 13945555.

It is an arithmetic number, because the mean of its divisors is an integer number (13945555).

Almost surely, 2^27891109 is an apocalyptic number.

It is an amenable number.

27891109 is a deficient number, since it is larger than the sum of its proper divisors (1).

27891109 is an equidigital number, since it uses as much as digits as its factorization.

27891109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 27891109 is about 5281.2033666580. The cubic root of 27891109 is about 303.2647462634.

It can be divided in two parts, 27 and 891109, that added together give a square (891136 = 944²).

The spelling of 27891109 in words is "twenty-seven million, eight hundred ninety-one thousand, one hundred nine".