28247920 has 20 divisors (see below), whose sum is σ = 65676600. Its totient is φ = 11299136.

The previous prime is 28247917. The next prime is 28247953. The reversal of 28247920 is 2974282.

It is a tau number, because it is divible by the number of its divisors (20).

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 3 ways as a sum of consecutive naturals, for example, 176470 + ... + 176629.

It is an arithmetic number, because the mean of its divisors is an integer number (3283830).

Almost surely, 2^28247920 is an apocalyptic number.

28247920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28247920 is an abundant number, since it is smaller than the sum of its proper divisors (37428680).

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

28247920 is a wasteful number, since it uses less digits than its factorization.

28247920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353112 (or 353106 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 28247920 is about 5314.8772328249. The cubic root of 28247920 is about 304.5524925164.

The spelling of 28247920 in words is "twenty-eight million, two hundred forty-seven thousand, nine hundred twenty".