28000278005 has 24 divisors (see below), whose sum is σ = 39105189720. Its totient is φ = 19190814720.

The previous prime is 28000277959. The next prime is 28000278083. The reversal of 28000278005 is 50087200082.

It can be written as a sum of positive squares in 4 ways, for example, as 537822481 + 27462455524 = 23191^2 + 165718^2 .

It is not a de Polignac number, because 28000278005 - 2⁸ = 28000277749 is a prime.

It is a super-3 number, since 3×28000278005³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 494765 + ... + 548445.

It is an arithmetic number, because the mean of its divisors is an integer number (1629382905).

Almost surely, 2^28000278005 is an apocalyptic number.

It is an amenable number.

28000278005 is a deficient number, since it is larger than the sum of its proper divisors (11104911715).

28000278005 is a wasteful number, since it uses less digits than its factorization.

28000278005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55829 (or 55822 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 32.

Adding to 28000278005 its reverse (50087200082), we get a palindrome (78087478087).

The spelling of 28000278005 in words is "twenty-eight billion, two hundred seventy-eight thousand, five".