28668013 has 4 divisors (see below), whose sum is σ = 31274208. Its totient is φ = 26061820.

The previous prime is 28667953. The next prime is 28668019. The reversal of 28668013 is 31086682.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28668013 - 2¹³ = 28659821 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28668013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28668019) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1303081 + ... + 1303102.

It is an arithmetic number, because the mean of its divisors is an integer number (7818552).

Almost surely, 2^28668013 is an apocalyptic number.

It is an amenable number.

28668013 is a deficient number, since it is larger than the sum of its proper divisors (2606195).

28668013 is a wasteful number, since it uses less digits than its factorization.

28668013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2606194.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 28668013 is about 5354.2518618384. The cubic root of 28668013 is about 306.0548017247.

The spelling of 28668013 in words is "twenty-eight million, six hundred sixty-eight thousand, thirteen".