27664991 has 2 divisors, whose sum is σ = 27664992. Its totient is φ = 27664990.

The previous prime is 27664961. The next prime is 27664997. The reversal of 27664991 is 19946672.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27664991 - 2¹⁰ = 27663967 is a prime.

It is a Sophie Germain 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 (27664997) by changing a digit.

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

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13832495 + 13832496.

It is an arithmetic number, because the mean of its divisors is an integer number (13832496).

Almost surely, 2^27664991 is an apocalyptic number.

27664991 is a deficient number, since it is larger than the sum of its proper divisors (1).

27664991 is an equidigital number, since it uses as much as digits as its factorization.

27664991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 44.

The square root of 27664991 is about 5259.7519903509. The cubic root of 27664991 is about 302.4429817629.

The spelling of 27664991 in words is "twenty-seven million, six hundred sixty-four thousand, nine hundred ninety-one".