28005040 has 80 divisors (see below), whose sum is σ = 76209408. Its totient is φ = 9370368.

The previous prime is 28005023. The next prime is 28005073. The reversal of 28005040 is 4050082.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

28005040 is a modest number, since divided by 5040 gives 2800 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 28004999 and 28005017.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23499 + ... + 24661.

Almost surely, 2^28005040 is an apocalyptic number.

28005040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28005040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38104704).

28005040 is an abundant number, since it is smaller than the sum of its proper divisors (48204368).

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

28005040 is a wasteful number, since it uses less digits than its factorization.

28005040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1226 (or 1220 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 28005040 is about 5291.9788359365. The cubic root of 28005040 is about 303.6771156283.

The spelling of 28005040 in words is "twenty-eight million, five thousand, forty".