27997 has 2 divisors, whose sum is σ = 27998. Its totient is φ = 27996.

The previous prime is 27983. The next prime is 28001. The reversal of 27997 is 79972.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27556 + 441 = 166^2 + 21^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27997 is a prime.

It is a nialpdrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13998 + 13999.

It is an arithmetic number, because the mean of its divisors is an integer number (13999).

2²⁷⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

27997 is a deficient number, since it is larger than the sum of its proper divisors (1).

27997 is an equidigital number, since it uses as much as digits as its factorization.

27997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7938, while the sum is 34.

The square root of 27997 is about 167.3230408521. The cubic root of 27997 is about 30.3648051840.

It can be divided in two parts, 27 and 997, that added together give a 10-th power (1024 = 2¹⁰).

The spelling of 27997 in words is "twenty-seven thousand, nine hundred ninety-seven".