2172064548561 has 4 divisors (see below), whose sum is σ = 2896086064752. Its totient is φ = 1448043032372.

The previous prime is 2172064548527. The next prime is 2172064548617. The reversal of 2172064548561 is 1658454602712.

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 2172064548561 - 2¹⁴ = 2172064532177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2172064538561) 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, 362010758091 + ... + 362010758096.

It is an arithmetic number, because the mean of its divisors is an integer number (724021516188).

Almost surely, 2^{2172064548561} is an apocalyptic number.

It is an amenable number.

2172064548561 is a deficient number, since it is larger than the sum of its proper divisors (724021516191).

2172064548561 is an equidigital number, since it uses as much as digits as its factorization.

2172064548561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724021516190.

The product of its (nonzero) digits is 3225600, while the sum is 51.

The spelling of 2172064548561 in words is "two trillion, one hundred seventy-two billion, sixty-four million, five hundred forty-eight thousand, five hundred sixty-one".