28197856265 has 4 divisors (see below), whose sum is σ = 33837427524. Its totient is φ = 22558285008.

The previous prime is 28197856223. The next prime is 28197856303. The reversal of 28197856265 is 56265879182.

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 4364980624 + 23832875641 = 66068^2 + 154379^2 .

It is a cyclic number.

It is not a de Polignac number, because 28197856265 - 2¹⁴ = 28197839881 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2819785622 + ... + 2819785631.

It is an arithmetic number, because the mean of its divisors is an integer number (8459356881).

Almost surely, 2^28197856265 is an apocalyptic number.

It is an amenable number.

28197856265 is a deficient number, since it is larger than the sum of its proper divisors (5639571259).

28197856265 is an equidigital number, since it uses as much as digits as its factorization.

28197856265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5639571258.

The product of its digits is 14515200, while the sum is 59.

The spelling of 28197856265 in words is "twenty-eight billion, one hundred ninety-seven million, eight hundred fifty-six thousand, two hundred sixty-five".