27788561 has 2 divisors, whose sum is σ = 27788562. Its totient is φ = 27788560.

The previous prime is 27788539. The next prime is 27788567. The reversal of 27788561 is 16588772.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24690961 + 3097600 = 4969^2 + 1760^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27788561 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (27788567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13894280 + 13894281.

It is an arithmetic number, because the mean of its divisors is an integer number (13894281).

Almost surely, 2^27788561 is an apocalyptic number.

It is an amenable number.

27788561 is a deficient number, since it is larger than the sum of its proper divisors (1).

27788561 is an equidigital number, since it uses as much as digits as its factorization.

27788561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 188160, while the sum is 44.

The square root of 27788561 is about 5271.4856539689. The cubic root of 27788561 is about 302.8926158991.

The spelling of 27788561 in words is "twenty-seven million, seven hundred eighty-eight thousand, five hundred sixty-one".