28110881569 has 3 divisors (see below), whose sum is σ = 28111049233. Its totient is φ = 28110713906.

The previous prime is 28110881563. The next prime is 28110881581. The reversal of 28110881569 is 96518801182.

The square root of 28110881569 is 167663.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 28110881569 - 2¹¹ = 28110879521 is a prime.

It is a super-2 number, since 2×28110881569² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28110881563) by changing a digit.

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 2 ways as a sum of consecutive naturals, for example, 83832 + ... + 251494.

Almost surely, 2^28110881569 is an apocalyptic number.

28110881569 is the 167663-rd square number.

28110881569 is the 83832-nd centered octagonal number.

It is an amenable number.

28110881569 is a deficient number, since it is larger than the sum of its proper divisors (167664).

28110881569 is an frugal number, since it uses more digits than its factorization.

28110881569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335326 (or 167663 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 49.

Multiplying 28110881569 by its sum of digits (49), we get a square (1377433196881 = 1173641²).

The spelling of 28110881569 in words is "twenty-eight billion, one hundred ten million, eight hundred eighty-one thousand, five hundred sixty-nine".