27917777081 has 2 divisors, whose sum is σ = 27917777082. Its totient is φ = 27917777080.

The previous prime is 27917777059. The next prime is 27917777143. The reversal of 27917777081 is 18077771972.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27917063056 + 714025 = 167084^2 + 845^2 .

It is a cyclic number.

It is not a de Polignac number, because 27917777081 - 2¹⁴ = 27917760697 is a prime.

It is a super-2 number, since 2×27917777081² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (27917777581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13958888540 + 13958888541.

It is an arithmetic number, because the mean of its divisors is an integer number (13958888541).

Almost surely, 2^27917777081 is an apocalyptic number.

It is an amenable number.

27917777081 is a deficient number, since it is larger than the sum of its proper divisors (1).

27917777081 is an equidigital number, since it uses as much as digits as its factorization.

27917777081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2420208, while the sum is 56.

The spelling of 27917777081 in words is "twenty-seven billion, nine hundred seventeen million, seven hundred seventy-seven thousand, eighty-one".