27656621 has 2 divisors, whose sum is σ = 27656622. Its totient is φ = 27656620.

The previous prime is 27656617. The next prime is 27656623. The reversal of 27656621 is 12665672.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15132100 + 12524521 = 3890^2 + 3539^2 .

It is a cyclic number.

It is not a de Polignac number, because 27656621 - 2² = 27656617 is a prime.

Together with 27656623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27656623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13828310 + 13828311.

It is an arithmetic number, because the mean of its divisors is an integer number (13828311).

Almost surely, 2^27656621 is an apocalyptic number.

It is an amenable number.

27656621 is a deficient number, since it is larger than the sum of its proper divisors (1).

27656621 is an equidigital number, since it uses as much as digits as its factorization.

27656621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 35.

The square root of 27656621 is about 5258.9562652679. The cubic root of 27656621 is about 302.4124774685.

The spelling of 27656621 in words is "twenty-seven million, six hundred fifty-six thousand, six hundred twenty-one".