28128734460 has 96 divisors (see below), whose sum is σ = 87618827520. Its totient is φ = 7491806784.

The previous prime is 28128734437. The next prime is 28128734477. The reversal of 28128734460 is 6443782182.

It is a happy number.

28128734460 is a `hidden beast` number, since 2 + 81 + 2 + 87 + 34 + 460 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 415087 + ... + 478073.

It is an arithmetic number, because the mean of its divisors is an integer number (912696120).

Almost surely, 2^28128734460 is an apocalyptic number.

28128734460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28128734460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43809413760).

28128734460 is an abundant number, since it is smaller than the sum of its proper divisors (59490093060).

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

28128734460 is a wasteful number, since it uses less digits than its factorization.

28128734460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63832 (or 63824 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The spelling of 28128734460 in words is "twenty-eight billion, one hundred twenty-eight million, seven hundred thirty-four thousand, four hundred sixty".