28108780 has 96 divisors (see below), whose sum is σ = 71124480. Its totient is φ = 9131520.

The previous prime is 28108777. The next prime is 28108807. The reversal of 28108780 is 8780182.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 338619 + ... + 338701.

It is an arithmetic number, because the mean of its divisors is an integer number (740880).

Almost surely, 2^28108780 is an apocalyptic number.

28108780 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 28108780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35562240).

28108780 is an abundant number, since it is smaller than the sum of its proper divisors (43015700).

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

28108780 is a wasteful number, since it uses less digits than its factorization.

28108780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199 (or 197 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 28108780 is about 5301.7714020882. The cubic root of 28108780 is about 304.0516273121.

It can be divided in two parts, 2810 and 8780, that multiplied together give a triangular number (24671800 = T₇₀₂₄).

The spelling of 28108780 in words is "twenty-eight million, one hundred eight thousand, seven hundred eighty".