28393040 has 80 divisors (see below), whose sum is σ = 74245248. Its totient is φ = 10019328.

The previous prime is 28393037. The next prime is 28393051. The reversal of 28393040 is 4039382.

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

It is a junction number, because it is equal to n+sod(n) for n = 28392994 and 28393012.

It is a congruent number.

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, 23327 + ... + 24513.

Almost surely, 2^28393040 is an apocalyptic number.

28393040 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 28393040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37122624).

28393040 is an abundant number, since it is smaller than the sum of its proper divisors (45852208).

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

28393040 is a wasteful number, since it uses less digits than its factorization.

28393040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236 (or 1230 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 28393040 is about 5328.5119874126. The cubic root of 28393040 is about 305.0731348403.

The spelling of 28393040 in words is "twenty-eight million, three hundred ninety-three thousand, forty".