28129400 has 96 divisors (see below), whose sum is σ = 72912000. Its totient is φ = 10022400.

The previous prime is 28129397. The next prime is 28129417. The reversal of 28129400 is 492182.

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 28129400.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80426 + ... + 80774.

It is an arithmetic number, because the mean of its divisors is an integer number (759500).

Almost surely, 2^28129400 is an apocalyptic number.

28129400 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 28129400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36456000).

28129400 is an abundant number, since it is smaller than the sum of its proper divisors (44782600).

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

28129400 is a wasteful number, since it uses less digits than its factorization.

28129400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409 (or 400 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 28129400 is about 5303.7156786540. The cubic root of 28129400 is about 304.1259577303.

The spelling of 28129400 in words is "twenty-eight million, one hundred twenty-nine thousand, four hundred".