28072440 has 256 divisors, whose sum is σ = 108864000. Its totient is φ = 6359040.

The previous prime is 28072439. The next prime is 28072463. The reversal of 28072440 is 4427082.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 201891 + ... + 202029.

It is an arithmetic number, because the mean of its divisors is an integer number (425250).

Almost surely, 2^28072440 is an apocalyptic number.

28072440 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 28072440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54432000).

28072440 is an abundant number, since it is smaller than the sum of its proper divisors (80791560).

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

28072440 is a wasteful number, since it uses less digits than its factorization.

28072440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 28072440 is about 5298.3431372458. The cubic root of 28072440 is about 303.9205413292.

The spelling of 28072440 in words is "twenty-eight million, seventy-two thousand, four hundred forty".