561165552309 has 4 divisors (see below), whose sum is σ = 748220736416. Its totient is φ = 374110368204.

The previous prime is 561165552301. The next prime is 561165552319. The reversal of 561165552309 is 903255561165.

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 not a de Polignac number, because 561165552309 - 2³ = 561165552301 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561165552301) 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, 93527592049 + ... + 93527592054.

It is an arithmetic number, because the mean of its divisors is an integer number (187055184104).

Almost surely, 2^561165552309 is an apocalyptic number.

It is an amenable number.

561165552309 is a deficient number, since it is larger than the sum of its proper divisors (187055184107).

561165552309 is a wasteful number, since it uses less digits than its factorization.

561165552309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 187055184106.

The product of its (nonzero) digits is 1215000, while the sum is 48.

The spelling of 561165552309 in words is "five hundred sixty-one billion, one hundred sixty-five million, five hundred fifty-two thousand, three hundred nine".