28685356771 has 2 divisors, whose sum is σ = 28685356772. Its totient is φ = 28685356770.

The previous prime is 28685356769. The next prime is 28685356807. The reversal of 28685356771 is 17765358682.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28685356771 - 2¹ = 28685356769 is a prime.

Together with 28685356769, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (28685356741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14342678385 + 14342678386.

It is an arithmetic number, because the mean of its divisors is an integer number (14342678386).

Almost surely, 2^28685356771 is an apocalyptic number.

28685356771 is a deficient number, since it is larger than the sum of its proper divisors (1).

28685356771 is an equidigital number, since it uses as much as digits as its factorization.

28685356771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16934400, while the sum is 58.

The spelling of 28685356771 in words is "twenty-eight billion, six hundred eighty-five million, three hundred fifty-six thousand, seven hundred seventy-one".