28871730 has 48 divisors (see below), whose sum is σ = 75605400. Its totient is φ = 7643904.

The previous prime is 28871683. The next prime is 28871737. The reversal of 28871730 is 3717882.

It can be written as a sum of positive squares in 4 ways, for example, as 10131489 + 18740241 = 3183^2 + 4329^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28871737) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12334 + ... + 14486.

Almost surely, 2^28871730 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28871730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37802700).

28871730 is an abundant number, since it is smaller than the sum of its proper divisors (46733670).

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

28871730 is a wasteful number, since it uses less digits than its factorization.

28871730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2315 (or 2312 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The square root of 28871730 is about 5373.2420380995. The cubic root of 28871730 is about 306.7780405697.

The spelling of 28871730 in words is "twenty-eight million, eight hundred seventy-one thousand, seven hundred thirty".