28620561317 has 4 divisors (see below), whose sum is σ = 28620952800. Its totient is φ = 28620169836.

The previous prime is 28620561223. The next prime is 28620561331. The reversal of 28620561317 is 71316502682.

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: 71316502682 = 2 ⋅35658251341.

It is a cyclic number.

It is not a de Polignac number, because 28620561317 - 2¹² = 28620557221 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 (28620561367) 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, 49817 + ... + 244382.

It is an arithmetic number, because the mean of its divisors is an integer number (7155238200).

Almost surely, 2^28620561317 is an apocalyptic number.

It is an amenable number.

28620561317 is a deficient number, since it is larger than the sum of its proper divisors (391483).

28620561317 is an equidigital number, since it uses as much as digits as its factorization.

28620561317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 391482.

The product of its (nonzero) digits is 120960, while the sum is 41.

The spelling of 28620561317 in words is "twenty-eight billion, six hundred twenty million, five hundred sixty-one thousand, three hundred seventeen".