28442240 has 64 divisors (see below), whose sum is σ = 71604000. Its totient is φ = 10773504.

The previous prime is 28442231. The next prime is 28442273. The reversal of 28442240 is 4224482.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×28442240² = 1617922032435200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10991 + ... + 13329.

Almost surely, 2^28442240 is an apocalyptic number.

28442240 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 28442240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35802000).

28442240 is an abundant number, since it is smaller than the sum of its proper divisors (43161760).

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

28442240 is a wasteful number, since it uses less digits than its factorization.

28442240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2377 (or 2365 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 26.

The square root of 28442240 is about 5333.1266626623. The cubic root of 28442240 is about 305.2492453346.

It can be divided in two parts, 28442 and 240, that added together give a palindrome (28682).

The spelling of 28442240 in words is "twenty-eight million, four hundred forty-two thousand, two hundred forty".