28870920 has 192 divisors, whose sum is σ = 104832000. Its totient is φ = 6842880.

The previous prime is 28870859. The next prime is 28870927. The reversal of 28870920 is 2907882.

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

It is not an unprimeable number, because it can be changed into a prime (28870927) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 144981 + ... + 145179.

It is an arithmetic number, because the mean of its divisors is an integer number (546000).

Almost surely, 2^28870920 is an apocalyptic number.

28870920 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 28870920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52416000).

28870920 is an abundant number, since it is smaller than the sum of its proper divisors (75961080).

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

28870920 is a wasteful number, since it uses less digits than its factorization.

28870920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260 (or 253 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 28870920 is about 5373.1666640818. The cubic root of 28870920 is about 306.7751716441.

The spelling of 28870920 in words is "twenty-eight million, eight hundred seventy thousand, nine hundred twenty".