28431828 has 72 divisors (see below), whose sum is σ = 76396320. Its totient is φ = 8890560.

The previous prime is 28431791. The next prime is 28431829. The reversal of 28431828 is 82813482.

It is a happy number.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28431792 and 28431801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28431829) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134643 + ... + 134853.

It is an arithmetic number, because the mean of its divisors is an integer number (1061060).

Almost surely, 2^28431828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28431828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38198160).

28431828 is an abundant number, since it is smaller than the sum of its proper divisors (47964492).

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

28431828 is a wasteful number, since it uses less digits than its factorization.

28431828 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437 (or 432 counting only the distinct ones).

The product of its digits is 24576, while the sum is 36.

The square root of 28431828 is about 5332.1504104817. The cubic root of 28431828 is about 305.2119927243.

The spelling of 28431828 in words is "twenty-eight million, four hundred thirty-one thousand, eight hundred twenty-eight".