27509681 has 2 divisors, whose sum is σ = 27509682. Its totient is φ = 27509680.

The previous prime is 27509639. The next prime is 27509683. The reversal of 27509681 is 18690572.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22848400 + 4661281 = 4780^2 + 2159^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27509681 is a prime.

It is a super-2 number, since 2×27509681² = 1513565097443522, which contains 22 as substring.

Together with 27509683, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (27509683) 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, 13754840 + 13754841.

It is an arithmetic number, because the mean of its divisors is an integer number (13754841).

Almost surely, 2^27509681 is an apocalyptic number.

It is an amenable number.

27509681 is a deficient number, since it is larger than the sum of its proper divisors (1).

27509681 is an equidigital number, since it uses as much as digits as its factorization.

27509681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 27509681 is about 5244.9672067612. The cubic root of 27509681 is about 301.8759522994.

The spelling of 27509681 in words is "twenty-seven million, five hundred nine thousand, six hundred eighty-one".