27963688981 has 4 divisors (see below), whose sum is σ = 27967680000. Its totient is φ = 27959697964.

The previous prime is 27963688979. The next prime is 27963688993. The reversal of 27963688981 is 18988636972.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27963688981 - 2¹ = 27963688979 is a prime.

It is a super-2 number, since 2×27963688981² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27963628981) 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, 1984981 + ... + 1999018.

It is an arithmetic number, because the mean of its divisors is an integer number (6991920000).

Almost surely, 2^27963688981 is an apocalyptic number.

It is an amenable number.

27963688981 is a deficient number, since it is larger than the sum of its proper divisors (3991019).

27963688981 is an equidigital number, since it uses as much as digits as its factorization.

27963688981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3991018.

The product of its digits is 62705664, while the sum is 67.

The spelling of 27963688981 in words is "twenty-seven billion, nine hundred sixty-three million, six hundred eighty-eight thousand, nine hundred eighty-one".