27987191 has 2 divisors, whose sum is σ = 27987192. Its totient is φ = 27987190.

The previous prime is 27987149. The next prime is 27987217. The reversal of 27987191 is 19178972.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27987191 - 2¹⁴ = 27970807 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 (27987101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13993595 + 13993596.

It is an arithmetic number, because the mean of its divisors is an integer number (13993596).

Almost surely, 2^27987191 is an apocalyptic number.

27987191 is a deficient number, since it is larger than the sum of its proper divisors (1).

27987191 is an equidigital number, since it uses as much as digits as its factorization.

27987191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 44.

The square root of 27987191 is about 5290.2921469424. The cubic root of 27987191 is about 303.6125857581.

The spelling of 27987191 in words is "twenty-seven million, nine hundred eighty-seven thousand, one hundred ninety-one".