28250040 has 192 divisors, whose sum is σ = 105408000. Its totient is φ = 5930496.

The previous prime is 28250029. The next prime is 28250041. The reversal of 28250040 is 4005282.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 28249989 and 28250016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28250041) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 141861 + ... + 142059.

It is an arithmetic number, because the mean of its divisors is an integer number (549000).

Almost surely, 2^28250040 is an apocalyptic number.

28250040 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 28250040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52704000).

28250040 is an abundant number, since it is smaller than the sum of its proper divisors (77157960).

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

28250040 is a wasteful number, since it uses less digits than its factorization.

28250040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 229 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 28250040 is about 5315.0766692495. The cubic root of 28250040 is about 304.5601111910.

The spelling of 28250040 in words is "twenty-eight million, two hundred fifty thousand, forty".