28303920 has 120 divisors (see below), whose sum is σ = 100105200. Its totient is φ = 7147008.

The previous prime is 28303903. The next prime is 28303943. The reversal of 28303920 is 2930382.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×28303920² = 1602223774732800, which contains 22 as substring.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 12646 + ... + 14714.

It is an arithmetic number, because the mean of its divisors is an integer number (834210).

Almost surely, 2^28303920 is an apocalyptic number.

28303920 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 28303920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50052600).

28303920 is an abundant number, since it is smaller than the sum of its proper divisors (71801280).

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

28303920 is a wasteful number, since it uses less digits than its factorization.

28303920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2107 (or 2098 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 28303920 is about 5320.1428552248. The cubic root of 28303920 is about 304.7536127146.

The spelling of 28303920 in words is "twenty-eight million, three hundred three thousand, nine hundred twenty".