27564661 has 2 divisors, whose sum is σ = 27564662. Its totient is φ = 27564660.

The previous prime is 27564659. The next prime is 27564697. The reversal of 27564661 is 16646572.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14676561 + 12888100 = 3831^2 + 3590^2 .

It is a cyclic number.

It is not a de Polignac number, because 27564661 - 2¹ = 27564659 is a prime.

Together with 27564659, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 27564661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27564631) 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, 13782330 + 13782331.

It is an arithmetic number, because the mean of its divisors is an integer number (13782331).

Almost surely, 2^27564661 is an apocalyptic number.

It is an amenable number.

27564661 is a deficient number, since it is larger than the sum of its proper divisors (1).

27564661 is an equidigital number, since it uses as much as digits as its factorization.

27564661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60480, while the sum is 37.

The square root of 27564661 is about 5250.2058054899. The cubic root of 27564661 is about 302.0769251287.

The spelling of 27564661 in words is "twenty-seven million, five hundred sixty-four thousand, six hundred sixty-one".