26987309805 has 16 divisors (see below), whose sum is σ = 43787862144. Its totient is φ = 14190509760.

The previous prime is 26987309773. The next prime is 26987309819. The reversal of 26987309805 is 50890378962.

It is not a de Polignac number, because 26987309805 - 2⁵ = 26987309773 is a prime.

It is a super-2 number, since 2×26987309805² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 12669034 + ... + 12671163.

It is an arithmetic number, because the mean of its divisors is an integer number (2736741384).

Almost surely, 2^26987309805 is an apocalyptic number.

It is an amenable number.

26987309805 is a deficient number, since it is larger than the sum of its proper divisors (16800552339).

26987309805 is a wasteful number, since it uses less digits than its factorization.

26987309805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25340276.

The product of its (nonzero) digits is 6531840, while the sum is 57.

The spelling of 26987309805 in words is "twenty-six billion, nine hundred eighty-seven million, three hundred nine thousand, eight hundred five".