27657634561 has 2 divisors, whose sum is σ = 27657634562. Its totient is φ = 27657634560.

The previous prime is 27657634559. The next prime is 27657634567. The reversal of 27657634561 is 16543675672.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24737312961 + 2920321600 = 157281^2 + 54040^2 .

It is a cyclic number.

It is not a de Polignac number, because 27657634561 - 2¹ = 27657634559 is a prime.

Together with 27657634559, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 27657634499 and 27657634508.

It is not a weakly prime, because it can be changed into another prime (27657634567) 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, 13828817280 + 13828817281.

It is an arithmetic number, because the mean of its divisors is an integer number (13828817281).

Almost surely, 2^27657634561 is an apocalyptic number.

It is an amenable number.

27657634561 is a deficient number, since it is larger than the sum of its proper divisors (1).

27657634561 is an equidigital number, since it uses as much as digits as its factorization.

27657634561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6350400, while the sum is 52.

The spelling of 27657634561 in words is "twenty-seven billion, six hundred fifty-seven million, six hundred thirty-four thousand, five hundred sixty-one".