28517874885369 has 45 divisors (see below), whose sum is σ = 43617692617653. Its totient is φ = 18568433261448.

The previous prime is 28517874885233. The next prime is 28517874885371. The reversal of 28517874885369 is 96358847871582.

The square root of 28517874885369 is 5340213.

It is a perfect power (a square), and thus also a powerful number.

28517874885369 is a `hidden beast` number, since 2 + 8 + 5 + 1 + 7 + 8 + 74 + 8 + 8 + 536 + 9 = 666.

It is not a de Polignac number, because 28517874885369 - 2⁹ = 28517874884857 is a prime.

It is a super-2 number, since 2×28517874885369² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (28517874885469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 2066655532 + ... + 2066669330.

Almost surely, 2^{28517874885369} is an apocalyptic number.

28517874885369 is the 5340213-rd square number.

28517874885369 is the 2670107-th centered octagonal number.

It is an amenable number.

28517874885369 is a deficient number, since it is larger than the sum of its proper divisors (15099817732284).

28517874885369 is an frugal number, since it uses more digits than its factorization.

28517874885369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27696 (or 13845 counting only the distinct ones).

The product of its digits is 6502809600, while the sum is 81.

28517874885369 divided by its sum of digits (81) gives a square (352072529449 = 593357²).

The spelling of 28517874885369 in words is "twenty-eight trillion, five hundred seventeen billion, eight hundred seventy-four million, eight hundred eighty-five thousand, three hundred sixty-nine".