28778645576 has 32 divisors (see below), whose sum is σ = 55258467840. Its totient is φ = 14044725888.

The previous prime is 28778645569. The next prime is 28778645579. The reversal of 28778645576 is 67554687782.

It is not an unprimeable number, because it can be changed into a prime (28778645579) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33716 + ... + 242268.

It is an arithmetic number, because the mean of its divisors is an integer number (1726827120).

Almost surely, 2^28778645576 is an apocalyptic number.

It is an amenable number.

28778645576 is a deficient number, since it is larger than the sum of its proper divisors (26479822264).

28778645576 is a wasteful number, since it uses less digits than its factorization.

28778645576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208973 (or 208969 counting only the distinct ones).

The product of its digits is 158054400, while the sum is 65.

The spelling of 28778645576 in words is "twenty-eight billion, seven hundred seventy-eight million, six hundred forty-five thousand, five hundred seventy-six".