27806581747 has 4 divisors (see below), whose sum is σ = 31778950576. Its totient is φ = 23834212920.

The previous prime is 27806581697. The next prime is 27806581771. The reversal of 27806581747 is 74718560872.

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

It is a de Polignac number, because none of the positive numbers 2^k-27806581747 is a prime.

It is a Duffinian number.

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, 1986184404 + ... + 1986184417.

It is an arithmetic number, because the mean of its divisors is an integer number (7944737644).

Almost surely, 2^27806581747 is an apocalyptic number.

27806581747 is a deficient number, since it is larger than the sum of its proper divisors (3972368829).

27806581747 is an equidigital number, since it uses as much as digits as its factorization.

27806581747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3972368828.

The product of its (nonzero) digits is 5268480, while the sum is 55.

The spelling of 27806581747 in words is "twenty-seven billion, eight hundred six million, five hundred eighty-one thousand, seven hundred forty-seven".