28528613 has 4 divisors (see below), whose sum is σ = 28656768. Its totient is φ = 28400460.

The previous prime is 28528609. The next prime is 28528639. The reversal of 28528613 is 31682582.

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 28528613 - 2² = 28528609 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28528603) 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, 63743 + ... + 64188.

It is an arithmetic number, because the mean of its divisors is an integer number (7164192).

Almost surely, 2^28528613 is an apocalyptic number.

It is an amenable number.

28528613 is a deficient number, since it is larger than the sum of its proper divisors (128155).

28528613 is a wasteful number, since it uses less digits than its factorization.

28528613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128154.

The product of its digits is 23040, while the sum is 35.

The square root of 28528613 is about 5341.2183067162. The cubic root of 28528613 is about 305.5579253052.

The spelling of 28528613 in words is "twenty-eight million, five hundred twenty-eight thousand, six hundred thirteen".