28171320 has 128 divisors (see below), whose sum is σ = 90201600. Its totient is φ = 7023104.

The previous prime is 28171307. The next prime is 28171327. The reversal of 28171320 is 2317182.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28171327) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 162754 + ... + 162926.

It is an arithmetic number, because the mean of its divisors is an integer number (704700).

Almost surely, 2^28171320 is an apocalyptic number.

28171320 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 28171320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45100800).

28171320 is an abundant number, since it is smaller than the sum of its proper divisors (62030280).

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

28171320 is a wasteful number, since it uses less digits than its factorization.

28171320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 28171320 is about 5307.6661537817. Note that the first 3 decimals coincide. The cubic root of 28171320 is about 304.2769578975.

The spelling of 28171320 in words is "twenty-eight million, one hundred seventy-one thousand, three hundred twenty".