27806581243 has 4 divisors (see below), whose sum is σ = 31778950000. Its totient is φ = 23834212488.

The previous prime is 27806581217. The next prime is 27806581247. The reversal of 27806581243 is 34218560872.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 27806581243 - 2³³ = 19216646651 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 27806581193 and 27806581202.

It is not an unprimeable number, because it can be changed into a prime (27806581247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1986184368 + ... + 1986184381.

It is an arithmetic number, because the mean of its divisors is an integer number (7944737500).

Almost surely, 2^27806581243 is an apocalyptic number.

27806581243 is a deficient number, since it is larger than the sum of its proper divisors (3972368757).

27806581243 is an equidigital number, since it uses as much as digits as its factorization.

27806581243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3972368756.

The product of its (nonzero) digits is 645120, while the sum is 46.

The spelling of 27806581243 in words is "twenty-seven billion, eight hundred six million, five hundred eighty-one thousand, two hundred forty-three".