28178887860 has 72 divisors (see below), whose sum is σ = 85561224840. Its totient is φ = 7506874368.

The previous prime is 28178887853. The next prime is 28178887883. The reversal of 28178887860 is 6878887182.

It can be written as a sum of positive squares in 4 ways, for example, as 3869088804 + 24309799056 = 62202^2 + 155916^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 104044 + ... + 259196.

It is an arithmetic number, because the mean of its divisors is an integer number (1188350345).

Almost surely, 2^28178887860 is an apocalyptic number.

28178887860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28178887860 is an abundant number, since it is smaller than the sum of its proper divisors (57382336980).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28178887860 is a wasteful number, since it uses less digits than its factorization.

28178887860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156177 (or 156172 counting only the distinct ones).

The product of its (nonzero) digits is 19267584, while the sum is 63.

The spelling of 28178887860 in words is "twenty-eight billion, one hundred seventy-eight million, eight hundred eighty-seven thousand, eight hundred sixty".