28556513 has 4 divisors (see below), whose sum is σ = 28632240. Its totient is φ = 28480788.

The previous prime is 28556497. The next prime is 28556519. The reversal of 28556513 is 31565582.

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, and also an emirpimes, since its reverse is a distinct semiprime: 31565582 = 2 ⋅15782791.

It is a cyclic number.

It is not a de Polignac number, because 28556513 - 2⁴ = 28556497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28556519) 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, 37295 + ... + 38052.

It is an arithmetic number, because the mean of its divisors is an integer number (7158060).

Almost surely, 2^28556513 is an apocalyptic number.

It is an amenable number.

28556513 is a deficient number, since it is larger than the sum of its proper divisors (75727).

28556513 is an equidigital number, since it uses as much as digits as its factorization.

28556513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75726.

The product of its digits is 36000, while the sum is 35.

The square root of 28556513 is about 5343.8294321582. The cubic root of 28556513 is about 305.6575012239.

The spelling of 28556513 in words is "twenty-eight million, five hundred fifty-six thousand, five hundred thirteen".