26879999981 has 2 divisors, whose sum is σ = 26879999982. Its totient is φ = 26879999980.

The previous prime is 26879999977. The next prime is 26879999989. The reversal of 26879999981 is 18999997862.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26160151081 + 719848900 = 161741^2 + 26830^2 .

It is a cyclic number.

It is not a de Polignac number, because 26879999981 - 2² = 26879999977 is a prime.

It is a super-3 number, since 3×26879999981³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (26879999989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13439999990 + 13439999991.

It is an arithmetic number, because the mean of its divisors is an integer number (13439999991).

Almost surely, 2^26879999981 is an apocalyptic number.

It is an amenable number.

26879999981 is a deficient number, since it is larger than the sum of its proper divisors (1).

26879999981 is an equidigital number, since it uses as much as digits as its factorization.

26879999981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 317447424, while the sum is 77.

The spelling of 26879999981 in words is "twenty-six billion, eight hundred seventy-nine million, nine hundred ninety-nine thousand, nine hundred eighty-one".