561601566161 has 8 divisors (see below), whose sum is σ = 562545195264. Its totient is φ = 560658344400.

The previous prime is 561601566151. The next prime is 561601566241. The reversal of 561601566161 is 161665106165.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 561601566161 - 2³⁴ = 544421696977 is a prime.

It is a super-3 number, since 3×561601566161³ (a number of 36 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561601566101) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2723456 + ... + 2922398.

It is an arithmetic number, because the mean of its divisors is an integer number (70318149408).

Almost surely, 2^561601566161 is an apocalyptic number.

It is an amenable number.

561601566161 is a deficient number, since it is larger than the sum of its proper divisors (943629103).

561601566161 is a wasteful number, since it uses less digits than its factorization.

561601566161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203671.

The product of its (nonzero) digits is 194400, while the sum is 44.

The spelling of 561601566161 in words is "five hundred sixty-one billion, six hundred one million, five hundred sixty-six thousand, one hundred sixty-one".