2175204409561 has 4 divisors (see below), whose sum is σ = 2175218082724. Its totient is φ = 2175190736400.

The previous prime is 2175204409529. The next prime is 2175204409583. The reversal of 2175204409561 is 1659044025712.

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 1058841000000 + 1116363409561 = 1029000^2 + 1056581^2 .

It is a cyclic number.

It is not a de Polignac number, because 2175204409561 - 2⁵ = 2175204409529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2175204409361) 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, 6595110 + ... + 6917071.

It is an arithmetic number, because the mean of its divisors is an integer number (543804520681).

Almost surely, 2^{2175204409561} is an apocalyptic number.

It is an amenable number.

2175204409561 is a deficient number, since it is larger than the sum of its proper divisors (13673163).

2175204409561 is a wasteful number, since it uses less digits than its factorization.

2175204409561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13673162.

The product of its (nonzero) digits is 604800, while the sum is 46.

The spelling of 2175204409561 in words is "two trillion, one hundred seventy-five billion, two hundred four million, four hundred nine thousand, five hundred sixty-one".