28730013 has 16 divisors (see below), whose sum is σ = 43048320. Its totient is φ = 16910784.

The previous prime is 28730011. The next prime is 28730021. The reversal of 28730013 is 31003782.

It is not a de Polignac number, because 28730013 - 2¹ = 28730011 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28730011) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15118 + ... + 16911.

It is an arithmetic number, because the mean of its divisors is an integer number (2690520).

Almost surely, 2^28730013 is an apocalyptic number.

28730013 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

28730013 is a deficient number, since it is larger than the sum of its proper divisors (14318307).

28730013 is a wasteful number, since it uses less digits than its factorization.

28730013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32068.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 28730013 is about 5360.0385259809. The cubic root of 28730013 is about 306.2752766587.

Adding to 28730013 its reverse (31003782), we get a palindrome (59733795).

The spelling of 28730013 in words is "twenty-eight million, seven hundred thirty thousand, thirteen".