561578766108857 has 4 divisors (see below), whose sum is σ = 641804304124416. Its totient is φ = 481353228093300.

The previous prime is 561578766108839. The next prime is 561578766108889. The reversal of 561578766108857 is 758801667875165.

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 561578766108857 - 2⁸ = 561578766108601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561578766108817) 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, 40112769007769 + ... + 40112769007782.

It is an arithmetic number, because the mean of its divisors is an integer number (160451076031104).

Almost surely, 2^{561578766108857} is an apocalyptic number.

It is an amenable number.

561578766108857 is a deficient number, since it is larger than the sum of its proper divisors (80225538015559).

561578766108857 is an equidigital number, since it uses as much as digits as its factorization.

561578766108857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80225538015558.

The product of its (nonzero) digits is 4741632000, while the sum is 80.

The spelling of 561578766108857 in words is "five hundred sixty-one trillion, five hundred seventy-eight billion, seven hundred sixty-six million, one hundred eight thousand, eight hundred fifty-seven".