28778178565 has 16 divisors (see below), whose sum is σ = 37277884800. Its totient is φ = 21262196032.

The previous prime is 28778178529. The next prime is 28778178593. The reversal of 28778178565 is 56587187782.

It is a cyclic number.

It is not a de Polignac number, because 28778178565 - 2⁹ = 28778178053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28778178497 and 28778178506.

It is a congruent 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 15 ways as a sum of consecutive naturals, for example, 4311235 + ... + 4317904.

It is an arithmetic number, because the mean of its divisors is an integer number (2329867800).

Almost surely, 2^28778178565 is an apocalyptic number.

It is an amenable number.

28778178565 is a deficient number, since it is larger than the sum of its proper divisors (8499706235).

28778178565 is a wasteful number, since it uses less digits than its factorization.

28778178565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8629196.

The product of its digits is 52684800, while the sum is 64.

The spelling of 28778178565 in words is "twenty-eight billion, seven hundred seventy-eight million, one hundred seventy-eight thousand, five hundred sixty-five".