561404363404165 has 4 divisors (see below), whose sum is σ = 673685236085004. Its totient is φ = 449123490723328.

The previous prime is 561404363404163. The next prime is 561404363404193.

561404363404165 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 306959019900516 + 254445343503649 = 17520246^2 + 15951343^2 .

It is a cyclic number.

It is not a de Polignac number, because 561404363404165 - 2¹ = 561404363404163 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 (561404363404163) 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, 56140436340412 + ... + 56140436340421.

It is an arithmetic number, because the mean of its divisors is an integer number (168421309021251).

Almost surely, 2^{561404363404165} is an apocalyptic number.

It is an amenable number.

561404363404165 is a deficient number, since it is larger than the sum of its proper divisors (112280872680839).

561404363404165 is a wasteful number, since it uses less digits than its factorization.

561404363404165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112280872680838.

The product of its (nonzero) digits is 12441600, while the sum is 52.

The spelling of 561404363404165 in words is "five hundred sixty-one trillion, four hundred four billion, three hundred sixty-three million, four hundred four thousand, one hundred sixty-five".