28127396777 has 4 divisors (see below), whose sum is σ = 28405885956. Its totient is φ = 27848907600.

The previous prime is 28127396741. The next prime is 28127396779. The reversal of 28127396777 is 77769372182.

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

It can be written as a sum of positive squares in 2 ways, for example, as 21890977936 + 6236418841 = 147956^2 + 78971^2 .

It is a cyclic number.

It is not a de Polignac number, because 28127396777 - 2²² = 28123202473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28127396779) 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, 139244438 + ... + 139244639.

It is an arithmetic number, because the mean of its divisors is an integer number (7101471489).

Almost surely, 2^28127396777 is an apocalyptic number.

It is an amenable number.

28127396777 is a deficient number, since it is larger than the sum of its proper divisors (278489179).

28127396777 is a wasteful number, since it uses less digits than its factorization.

28127396777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278489178.

The product of its digits is 12446784, while the sum is 59.

The spelling of 28127396777 in words is "twenty-eight billion, one hundred twenty-seven million, three hundred ninety-six thousand, seven hundred seventy-seven".