28315820 has 24 divisors (see below), whose sum is σ = 64037904. Its totient is φ = 10454976.

The previous prime is 28315817. The next prime is 28315853. The reversal of 28315820 is 2851382.

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, 54194 + ... + 54713.

It is an arithmetic number, because the mean of its divisors is an integer number (2668246).

Almost surely, 2^28315820 is an apocalyptic number.

28315820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28315820 is an abundant number, since it is smaller than the sum of its proper divisors (35722084).

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

28315820 is a wasteful number, since it uses less digits than its factorization.

28315820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108929 (or 108927 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 28315820 is about 5321.2611287175. The cubic root of 28315820 is about 304.7963165740.

The spelling of 28315820 in words is "twenty-eight million, three hundred fifteen thousand, eight hundred twenty".