28073840 has 40 divisors (see below), whose sum is σ = 66797808. Its totient is φ = 10967040.

The previous prime is 28073839. The next prime is 28073863. The reversal of 28073840 is 4837082.

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

It is a junction number, because it is equal to n+sod(n) for n = 28073797 and 28073806.

It is a congruent number.

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, 641 + ... + 7520.

Almost surely, 2^28073840 is an apocalyptic number.

28073840 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 28073840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33398904).

28073840 is an abundant number, since it is smaller than the sum of its proper divisors (38723968).

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

28073840 is a wasteful number, since it uses less digits than its factorization.

28073840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8217 (or 8211 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 32.

The square root of 28073840 is about 5298.4752523721. The cubic root of 28073840 is about 303.9255935166.

The spelling of 28073840 in words is "twenty-eight million, seventy-three thousand, eight hundred forty".