28917921233 has 4 divisors (see below), whose sum is σ = 28928686080. Its totient is φ = 28907156388.

The previous prime is 28917921223. The next prime is 28917921259. The reversal of 28917921233 is 33212971982.

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: 33212971982 = 2 ⋅16606485991.

It is a cyclic number.

It is not a de Polignac number, because 28917921233 - 2¹⁰ = 28917920209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28917921223) 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, 5378393 + ... + 5383766.

It is an arithmetic number, because the mean of its divisors is an integer number (7232171520).

Almost surely, 2^28917921233 is an apocalyptic number.

It is an amenable number.

28917921233 is a deficient number, since it is larger than the sum of its proper divisors (10764847).

28917921233 is a wasteful number, since it uses less digits than its factorization.

28917921233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10764846.

The product of its digits is 326592, while the sum is 47.

The spelling of 28917921233 in words is "twenty-eight billion, nine hundred seventeen million, nine hundred twenty-one thousand, two hundred thirty-three".