28458220 has 72 divisors (see below), whose sum is σ = 70670880. Its totient is φ = 9596160.

The previous prime is 28458173. The next prime is 28458229. The reversal of 28458220 is 2285482.

It is not an unprimeable number, because it can be changed into a prime (28458229) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 69376 + ... + 69784.

It is an arithmetic number, because the mean of its divisors is an integer number (981540).

Almost surely, 2^28458220 is an apocalyptic number.

28458220 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 28458220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35335440).

28458220 is an abundant number, since it is smaller than the sum of its proper divisors (42212660).

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

28458220 is a wasteful number, since it uses less digits than its factorization.

28458220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503 (or 494 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 31.

The square root of 28458220 is about 5334.6246353422. The cubic root of 28458220 is about 305.3064017528.

The spelling of 28458220 in words is "twenty-eight million, four hundred fifty-eight thousand, two hundred twenty".