6561808349205 has 8 divisors (see below), whose sum is σ = 10498893358752. Its totient is φ = 3499631119568.

The previous prime is 6561808349189. The next prime is 6561808349273. The reversal of 6561808349205 is 5029438081656.

6561808349205 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 6561808349205 - 2⁴ = 6561808349189 is a prime.

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, 218726944959 + ... + 218726944988.

It is an arithmetic number, because the mean of its divisors is an integer number (1312361669844).

Almost surely, 2^{6561808349205} is an apocalyptic number.

It is an amenable number.

6561808349205 is a deficient number, since it is larger than the sum of its proper divisors (3937085009547).

6561808349205 is a wasteful number, since it uses less digits than its factorization.

6561808349205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437453889955.

The product of its (nonzero) digits is 12441600, while the sum is 57.

The spelling of 6561808349205 in words is "six trillion, five hundred sixty-one billion, eight hundred eight million, three hundred forty-nine thousand, two hundred five".