26604545881 has 3 divisors (see below), whose sum is σ = 26604708991. Its totient is φ = 26604382772.

The previous prime is 26604545873. The next prime is 26604545887. The reversal of 26604545881 is 18854540662.

The square root of 26604545881 is 163109.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18854540662 = 2 ⋅9427270331.

It can be written as a sum of positive squares in only one way, i.e., 17779822281 + 8824723600 = 133341^2 + 93940^2 .

It is not a de Polignac number, because 26604545881 - 2³ = 26604545873 is a prime.

It is a super-2 number, since 2×26604545881² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26604545887) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 81555 + ... + 244663.

Almost surely, 2^26604545881 is an apocalyptic number.

26604545881 is the 163109-th square number.

26604545881 is the 81555-th centered octagonal number.

It is an amenable number.

26604545881 is a deficient number, since it is larger than the sum of its proper divisors (163110).

26604545881 is an frugal number, since it uses more digits than its factorization.

26604545881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326218 (or 163109 counting only the distinct ones).

The product of its (nonzero) digits is 1843200, while the sum is 49.

Multiplying 26604545881 by its sum of digits (49), we get a square (1303622748169 = 1141763²).

The spelling of 26604545881 in words is "twenty-six billion, six hundred four million, five hundred forty-five thousand, eight hundred eighty-one".