28311330 has 32 divisors (see below), whose sum is σ = 71524800. Its totient is φ = 7152192.

The previous prime is 28311323. The next prime is 28311331. The reversal of 28311330 is 3311382.

It is a happy number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28311297 and 28311306.

It is not an unprimeable number, because it can be changed into a prime (28311331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24265 + ... + 25404.

It is an arithmetic number, because the mean of its divisors is an integer number (2235150).

Almost surely, 2^28311330 is an apocalyptic number.

28311330 is an abundant number, since it is smaller than the sum of its proper divisors (43213470).

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

28311330 is a wasteful number, since it uses less digits than its factorization.

28311330 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49698.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 28311330 is about 5320.8392195217. The cubic root of 28311330 is about 304.7802053471.

The spelling of 28311330 in words is "twenty-eight million, three hundred eleven thousand, three hundred thirty".