27768410781 has 4 divisors (see below), whose sum is σ = 37024547712. Its totient is φ = 18512273852.

The previous prime is 27768410779. The next prime is 27768410783. The reversal of 27768410781 is 18701486772.

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 an interprime number because it is at equal distance from previous prime (27768410779) and next prime (27768410783).

It is a cyclic number.

It is not a de Polignac number, because 27768410781 - 2¹ = 27768410779 is a prime.

It is a super-2 number, since 2×27768410781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27768410783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4628068461 + ... + 4628068466.

It is an arithmetic number, because the mean of its divisors is an integer number (9256136928).

Almost surely, 2^27768410781 is an apocalyptic number.

It is an amenable number.

27768410781 is a deficient number, since it is larger than the sum of its proper divisors (9256136931).

27768410781 is an equidigital number, since it uses as much as digits as its factorization.

27768410781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9256136930.

The product of its (nonzero) digits is 1053696, while the sum is 51.

The spelling of 27768410781 in words is "twenty-seven billion, seven hundred sixty-eight million, four hundred ten thousand, seven hundred eighty-one".