28513128 has 64 divisors (see below), whose sum is σ = 83381760. Its totient is φ = 7955136.

The previous prime is 28513127. The next prime is 28513141. The reversal of 28513128 is 82131582.

It is a junction number, because it is equal to n+sod(n) for n = 28513095 and 28513104.

It is not an unprimeable number, because it can be changed into a prime (28513127) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5251 + ... + 9197.

It is an arithmetic number, because the mean of its divisors is an integer number (1302840).

Almost surely, 2^28513128 is an apocalyptic number.

28513128 is a gapful number since it is divisible by the number (28) 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 28513128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41690880).

28513128 is an abundant number, since it is smaller than the sum of its proper divisors (54868632).

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

28513128 is a wasteful number, since it uses less digits than its factorization.

28513128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4006 (or 4002 counting only the distinct ones).

The product of its digits is 3840, while the sum is 30.

The square root of 28513128 is about 5339.7685343093. The cubic root of 28513128 is about 305.5026308678.

It can be divided in two parts, 285 and 13128, that multiplied together give a triangular number (3741480 = T₂₇₃₅).

The spelling of 28513128 in words is "twenty-eight million, five hundred thirteen thousand, one hundred twenty-eight".