26855809 has 4 divisors (see below), whose sum is σ = 26888004. Its totient is φ = 26823616.

The previous prime is 26855791. The next prime is 26855831. The reversal of 26855809 is 90855862.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90855862 = 2 ⋅45427931.

It can be written as a sum of positive squares in 2 ways, for example, as 25280784 + 1575025 = 5028^2 + 1255^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-26855809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (26855849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14812 + ... + 16525.

It is an arithmetic number, because the mean of its divisors is an integer number (6722001).

Almost surely, 2^26855809 is an apocalyptic number.

It is an amenable number.

26855809 is a deficient number, since it is larger than the sum of its proper divisors (32195).

26855809 is an equidigital number, since it uses as much as digits as its factorization.

26855809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32194.

The product of its (nonzero) digits is 172800, while the sum is 43.

The square root of 26855809 is about 5182.2590633815. The cubic root of 26855809 is about 299.4650057636.

The spelling of 26855809 in words is "twenty-six million, eight hundred fifty-five thousand, eight hundred nine".