28123200 has 420 divisors, whose sum is σ = 121952512. Its totient is φ = 6220800.

The previous prime is 28123189. The next prime is 28123201. The reversal of 28123200 is 232182.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (420).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (28123201) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 907185 + ... + 907215.

Almost surely, 2^28123200 is an apocalyptic number.

28123200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

28123200 is the 2835-th nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28123200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60976256).

28123200 is an abundant number, since it is smaller than the sum of its proper divisors (93829312).

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

28123200 is a wasteful number, since it uses less digits than its factorization.

28123200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72 (or 48 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 28123200 is about 5303.1311505562. The cubic root of 28123200 is about 304.1036119581.

Adding to 28123200 its reverse (232182), we get a palindrome (28355382).

The spelling of 28123200 in words is "twenty-eight million, one hundred twenty-three thousand, two hundred".