28556565671 has 2 divisors, whose sum is σ = 28556565672. Its totient is φ = 28556565670.

The previous prime is 28556565649. The next prime is 28556565689. The reversal of 28556565671 is 17656565582.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28556565671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28556565571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14278282835 + 14278282836.

It is an arithmetic number, because the mean of its divisors is an integer number (14278282836).

Almost surely, 2^28556565671 is an apocalyptic number.

28556565671 is a deficient number, since it is larger than the sum of its proper divisors (1).

28556565671 is an equidigital number, since it uses as much as digits as its factorization.

28556565671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120000, while the sum is 56.

The spelling of 28556565671 in words is "twenty-eight billion, five hundred fifty-six million, five hundred sixty-five thousand, six hundred seventy-one".