6561768944026 has 8 divisors (see below), whose sum is σ = 9842683969044. Its totient is φ = 3280874287680.

The previous prime is 6561768944011. The next prime is 6561768944053. The reversal of 6561768944026 is 6204498671656.

It is a Cunningham number, because it is equal to 2561595²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 6561768944025 + 1 = 2561595^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4259565 + ... + 5591728.

Almost surely, 2^{6561768944026} is an apocalyptic number.

6561768944026 is a deficient number, since it is larger than the sum of its proper divisors (3280915025018).

6561768944026 is a wasteful number, since it uses less digits than its factorization.

6561768944026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10184336.

The product of its (nonzero) digits is 104509440, while the sum is 64.

The spelling of 6561768944026 in words is "six trillion, five hundred sixty-one billion, seven hundred sixty-eight million, nine hundred forty-four thousand, twenty-six".