28917777788 has 12 divisors (see below), whose sum is σ = 50672615952. Its totient is φ = 14439887520.

The previous prime is 28917777787. The next prime is 28917777799. The reversal of 28917777788 is 88777771982.

It is a super-2 number, since 2×28917777788² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28917777781) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 4746920 + ... + 4753007.

It is an arithmetic number, because the mean of its divisors is an integer number (4222717996).

Almost surely, 2^28917777788 is an apocalyptic number.

It is an amenable number.

28917777788 is a deficient number, since it is larger than the sum of its proper divisors (21754838164).

28917777788 is a wasteful number, since it uses less digits than its factorization.

28917777788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9500692 (or 9500690 counting only the distinct ones).

The product of its digits is 154893312, while the sum is 71.

The spelling of 28917777788 in words is "twenty-eight billion, nine hundred seventeen million, seven hundred seventy-seven thousand, seven hundred eighty-eight".