27891491 has 2 divisors, whose sum is σ = 27891492. Its totient is φ = 27891490.

The previous prime is 27891467. The next prime is 27891499. The reversal of 27891491 is 19419872.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27891491 - 2¹⁸ = 27629347 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (27891499) 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, 13945745 + 13945746.

It is an arithmetic number, because the mean of its divisors is an integer number (13945746).

Almost surely, 2^27891491 is an apocalyptic number.

27891491 is a deficient number, since it is larger than the sum of its proper divisors (1).

27891491 is an equidigital number, since it uses as much as digits as its factorization.

27891491 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 41.

The square root of 27891491 is about 5281.2395325340. The cubic root of 27891491 is about 303.2661307740.

It can be divided in two parts, 27891 and 491, that added together give a palindrome (28382).

The spelling of 27891491 in words is "twenty-seven million, eight hundred ninety-one thousand, four hundred ninety-one".