28204720 has 40 divisors (see below), whose sum is σ = 67183200. Its totient is φ = 11005440.

The previous prime is 28204711. The next prime is 28204741. The reversal of 28204720 is 2740282.

It is a tau number, because it is divible by the number of its divisors (40).

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, 1020 + ... + 7579.

It is an arithmetic number, because the mean of its divisors is an integer number (1679580).

Almost surely, 2^28204720 is an apocalyptic number.

28204720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28204720 is an abundant number, since it is smaller than the sum of its proper divisors (38978480).

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

28204720 is a wasteful number, since it uses less digits than its factorization.

28204720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8653 (or 8647 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 28204720 is about 5310.8116140567. The cubic root of 28204720 is about 304.3971609583.

The spelling of 28204720 in words is "twenty-eight million, two hundred four thousand, seven hundred twenty".