28147680 has 144 divisors (see below), whose sum is σ = 104845104. Its totient is φ = 6819840.

The previous prime is 28147667. The next prime is 28147703. The reversal of 28147680 is 8674182.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 14952 + ... + 16728.

It is an arithmetic number, because the mean of its divisors is an integer number (728091).

Almost surely, 2^28147680 is an apocalyptic number.

28147680 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 28147680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52422552).

28147680 is an abundant number, since it is smaller than the sum of its proper divisors (76697424).

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

28147680 is a wasteful number, since it uses less digits than its factorization.

28147680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1809 (or 1798 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 28147680 is about 5305.4387188997. The cubic root of 28147680 is about 304.1918226103.

It can be divided in two parts, 281 and 47680, that added together give a square (47961 = 219²).

The spelling of 28147680 in words is "twenty-eight million, one hundred forty-seven thousand, six hundred eighty".