28864013 has 4 divisors (see below), whose sum is σ = 28912800. Its totient is φ = 28815228.

The previous prime is 28864009. The next prime is 28864027. The reversal of 28864013 is 31046882.

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: 31046882 = 2 ⋅15523441.

It is a cyclic number.

It is not a de Polignac number, because 28864013 - 2² = 28864009 is a prime.

It is a super-3 number, since 3×28864013³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28864093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23495 + ... + 24692.

It is an arithmetic number, because the mean of its divisors is an integer number (7228200).

Almost surely, 2^28864013 is an apocalyptic number.

It is an amenable number.

28864013 is a deficient number, since it is larger than the sum of its proper divisors (48787).

28864013 is an equidigital number, since it uses as much as digits as its factorization.

28864013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48786.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 28864013 is about 5372.5238947817. The cubic root of 28864013 is about 306.7507056750.

The spelling of 28864013 in words is "twenty-eight million, eight hundred sixty-four thousand, thirteen".