28170540 has 72 divisors (see below), whose sum is σ = 89958960. Its totient is φ = 7115904.

The previous prime is 28170539. The next prime is 28170557. The reversal of 28170540 is 4507182.

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, 699 + ... + 7538.

It is an arithmetic number, because the mean of its divisors is an integer number (1249430).

Almost surely, 2^28170540 is an apocalyptic number.

28170540 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 28170540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44979480).

28170540 is an abundant number, since it is smaller than the sum of its proper divisors (61788420).

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

28170540 is a wasteful number, since it uses less digits than its factorization.

28170540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8271 (or 8266 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 28170540 is about 5307.5926746502. The cubic root of 28170540 is about 304.2741496252.

The spelling of 28170540 in words is "twenty-eight million, one hundred seventy thousand, five hundred forty".