28221842 has 16 divisors (see below), whose sum is σ = 47672064. Its totient is φ = 12414000.

The previous prime is 28221839. The next prime is 28221847. The reversal of 28221842 is 24812282.

It is not an unprimeable number, because it can be changed into a prime (28221847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20009 + ... + 21372.

It is an arithmetic number, because the mean of its divisors is an integer number (2979504).

Almost surely, 2^28221842 is an apocalyptic number.

28221842 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

28221842 is a deficient number, since it is larger than the sum of its proper divisors (19450222).

28221842 is a wasteful number, since it uses less digits than its factorization.

28221842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41425.

The product of its digits is 4096, while the sum is 29.

The square root of 28221842 is about 5312.4233641531. The cubic root of 28221842 is about 304.4587444320.

It can be divided in two parts, 2822 and 1842, that added together give a palindrome (4664).

The spelling of 28221842 in words is "twenty-eight million, two hundred twenty-one thousand, eight hundred forty-two".