28563783505561 has 4 divisors (see below), whose sum is σ = 28563805468800. Its totient is φ = 28563761542324.

The previous prime is 28563783505553. The next prime is 28563783505627. The reversal of 28563783505561 is 16550538736582.

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 28563783505561 - 2³ = 28563783505553 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28563783505493 and 28563783505502.

It is not an unprimeable number, because it can be changed into a prime (28563783505501) 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, 8899201 + ... + 11675758.

It is an arithmetic number, because the mean of its divisors is an integer number (7140951367200).

Almost surely, 2^{28563783505561} is an apocalyptic number.

It is an amenable number.

28563783505561 is a deficient number, since it is larger than the sum of its proper divisors (21963239).

28563783505561 is a wasteful number, since it uses less digits than its factorization.

28563783505561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21963238.

The product of its (nonzero) digits is 181440000, while the sum is 64.

The spelling of 28563783505561 in words is "twenty-eight trillion, five hundred sixty-three billion, seven hundred eighty-three million, five hundred five thousand, five hundred sixty-one".