28127839657 has 2 divisors, whose sum is σ = 28127839658. Its totient is φ = 28127839656.

The previous prime is 28127839633. The next prime is 28127839693. The reversal of 28127839657 is 75693872182.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25222521856 + 2905317801 = 158816^2 + 53901^2 .

It is a cyclic number.

It is not a de Polignac number, because 28127839657 - 2¹⁹ = 28127315369 is a prime.

It is not a weakly prime, because it can be changed into another prime (28127839697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14063919828 + 14063919829.

It is an arithmetic number, because the mean of its divisors is an integer number (14063919829).

Almost surely, 2^28127839657 is an apocalyptic number.

It is an amenable number.

28127839657 is a deficient number, since it is larger than the sum of its proper divisors (1).

28127839657 is an equidigital number, since it uses as much as digits as its factorization.

28127839657 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10160640, while the sum is 58.

The spelling of 28127839657 in words is "twenty-eight billion, one hundred twenty-seven million, eight hundred thirty-nine thousand, six hundred fifty-seven".