26878138658 has 18 divisors (see below), whose sum is σ = 46902441393. Its totient is φ = 11518506720.

The previous prime is 26878138657. The next prime is 26878138667. The reversal of 26878138658 is 85683187862.

It can be written as a sum of positive squares in 2 ways, for example, as 18898825729 + 7979312929 = 137473^2 + 89327^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=115927.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 26878138658.

It is not an unprimeable number, because it can be changed into a prime (26878138657) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1614698 + ... + 1631258.

Almost surely, 2^26878138658 is an apocalyptic number.

26878138658 is a deficient number, since it is larger than the sum of its proper divisors (20024302735).

26878138658 is an frugal number, since it uses more digits than its factorization.

26878138658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33138 (or 16570 counting only the distinct ones).

The product of its digits is 30965760, while the sum is 62.

The spelling of 26878138658 in words is "twenty-six billion, eight hundred seventy-eight million, one hundred thirty-eight thousand, six hundred fifty-eight".