27711991 has 2 divisors, whose sum is σ = 27711992. Its totient is φ = 27711990.

The previous prime is 27711979. The next prime is 27711997. The reversal of 27711991 is 19911772.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27711991 - 2⁷ = 27711863 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27711991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27711997) 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, 13855995 + 13855996.

It is an arithmetic number, because the mean of its divisors is an integer number (13855996).

Almost surely, 2^27711991 is an apocalyptic number.

27711991 is a deficient number, since it is larger than the sum of its proper divisors (1).

27711991 is an equidigital number, since it uses as much as digits as its factorization.

27711991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7938, while the sum is 37.

The square root of 27711991 is about 5264.2179856081. The cubic root of 27711991 is about 302.6141581291.

The spelling of 27711991 in words is "twenty-seven million, seven hundred eleven thousand, nine hundred ninety-one".