28285308217 has 2 divisors, whose sum is σ = 28285308218. Its totient is φ = 28285308216.

The previous prime is 28285308211. The next prime is 28285308263. The reversal of 28285308217 is 71280358282.

It is an a-pointer prime, because the next prime (28285308263) can be obtained adding 28285308217 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25698975481 + 2586332736 = 160309^2 + 50856^2 .

It is a cyclic number.

It is not a de Polignac number, because 28285308217 - 2³ = 28285308209 is a prime.

It is not a weakly prime, because it can be changed into another prime (28285308211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14142654108 + 14142654109.

It is an arithmetic number, because the mean of its divisors is an integer number (14142654109).

Almost surely, 2^28285308217 is an apocalyptic number.

It is an amenable number.

28285308217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28285308217 is an equidigital number, since it uses as much as digits as its factorization.

28285308217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 430080, while the sum is 46.

The spelling of 28285308217 in words is "twenty-eight billion, two hundred eighty-five million, three hundred eight thousand, two hundred seventeen".