28305620 has 24 divisors (see below), whose sum is σ = 67933824. Its totient is φ = 9704736.

The previous prime is 28305619. The next prime is 28305631. The reversal of 28305620 is 2650382.

It is a self number, because there is not a number n which added to its sum of digits gives 28305620.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100952 + ... + 101231.

It is an arithmetic number, because the mean of its divisors is an integer number (2830576).

Almost surely, 2^28305620 is an apocalyptic number.

28305620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28305620 is an abundant number, since it is smaller than the sum of its proper divisors (39628204).

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

28305620 is a wasteful number, since it uses less digits than its factorization.

28305620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202199 (or 202197 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 28305620 is about 5320.3026229717. The cubic root of 28305620 is about 304.7597139987.

The spelling of 28305620 in words is "twenty-eight million, three hundred five thousand, six hundred twenty".