27728764778 has 16 divisors (see below), whose sum is σ = 48864676896. Its totient is φ = 11634446640.

The previous prime is 27728764769. The next prime is 27728764813. The reversal of 27728764778 is 87746782772.

It is a super-2 number, since 2×27728764778² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48476576 + ... + 48477147.

It is an arithmetic number, because the mean of its divisors is an integer number (3054042306).

Almost surely, 2^27728764778 is an apocalyptic number.

27728764778 is a deficient number, since it is larger than the sum of its proper divisors (21135912118).

27728764778 is a wasteful number, since it uses less digits than its factorization.

27728764778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96953749.

The product of its digits is 103262208, while the sum is 65.

The spelling of 27728764778 in words is "twenty-seven billion, seven hundred twenty-eight million, seven hundred sixty-four thousand, seven hundred seventy-eight".