27161676821 has 2 divisors, whose sum is σ = 27161676822. Its totient is φ = 27161676820.

The previous prime is 27161676811. The next prime is 27161676887. The reversal of 27161676821 is 12867616172.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24015700900 + 3145975921 = 154970^2 + 56089^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27161676821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27161676811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13580838410 + 13580838411.

It is an arithmetic number, because the mean of its divisors is an integer number (13580838411).

Almost surely, 2^27161676821 is an apocalyptic number.

It is an amenable number.

27161676821 is a deficient number, since it is larger than the sum of its proper divisors (1).

27161676821 is an equidigital number, since it uses as much as digits as its factorization.

27161676821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 47.

The spelling of 27161676821 in words is "twenty-seven billion, one hundred sixty-one million, six hundred seventy-six thousand, eight hundred twenty-one".