28017840 has 40 divisors (see below), whose sum is σ = 86856048. Its totient is φ = 7471360.

The previous prime is 28017839. The next prime is 28017863. The reversal of 28017840 is 4871082.

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

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 28017798 and 28017807.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58131 + ... + 58610.

Almost surely, 2^28017840 is an apocalyptic number.

28017840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28017840 is an abundant number, since it is smaller than the sum of its proper divisors (58838208).

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

28017840 is a wasteful number, since it uses less digits than its factorization.

28017840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116757 (or 116751 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 28017840 is about 5293.1880752529. The cubic root of 28017840 is about 303.7233748615.

The spelling of 28017840 in words is "twenty-eight million, seventeen thousand, eight hundred forty".