28077855820 has 48 divisors (see below), whose sum is σ = 70316725248. Its totient is φ = 9208140480.

The previous prime is 28077855811. The next prime is 28077855821. The reversal of 28077855820 is 2855877082.

It is not an unprimeable number, because it can be changed into a prime (28077855821) by changing a digit.

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, 4356696 + ... + 4363135.

It is an arithmetic number, because the mean of its divisors is an integer number (1464931776).

Almost surely, 2^28077855820 is an apocalyptic number.

28077855820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28077855820 is an abundant number, since it is smaller than the sum of its proper divisors (42238869428).

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

28077855820 is a wasteful number, since it uses less digits than its factorization.

28077855820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8719870 (or 8719868 counting only the distinct ones).

The product of its (nonzero) digits is 2508800, while the sum is 52.

The spelling of 28077855820 in words is "twenty-eight billion, seventy-seven million, eight hundred fifty-five thousand, eight hundred twenty".