6561205505606 has 16 divisors (see below), whose sum is σ = 9862396315200. Its totient is φ = 3273746457408.

The previous prime is 6561205505599. The next prime is 6561205505633. The reversal of 6561205505606 is 6065055021656.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 458426 + ... + 3651378.

It is an arithmetic number, because the mean of its divisors is an integer number (616399769700).

Almost surely, 2^{6561205505606} is an apocalyptic number.

6561205505606 is a deficient number, since it is larger than the sum of its proper divisors (3301190809594).

6561205505606 is a wasteful number, since it uses less digits than its factorization.

6561205505606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3195103.

The product of its (nonzero) digits is 1620000, while the sum is 47.

The spelling of 6561205505606 in words is "six trillion, five hundred sixty-one billion, two hundred five million, five hundred five thousand, six hundred six".