3205666055561 has 2 divisors, whose sum is σ = 3205666055562. Its totient is φ = 3205666055560.

The previous prime is 3205666055533. The next prime is 3205666055569. The reversal of 3205666055561 is 1655506665023.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2200419191161 + 1005246864400 = 1483381^2 + 1002620^2 .

It is a cyclic number.

It is not a de Polignac number, because 3205666055561 - 2²² = 3205661861257 is a prime.

It is not a weakly prime, because it can be changed into another prime (3205666055569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1602833027780 + 1602833027781.

It is an arithmetic number, because the mean of its divisors is an integer number (1602833027781).

Almost surely, 2^{3205666055561} is an apocalyptic number.

It is an amenable number.

3205666055561 is a deficient number, since it is larger than the sum of its proper divisors (1).

3205666055561 is an equidigital number, since it uses as much as digits as its factorization.

3205666055561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4860000, while the sum is 50.

The spelling of 3205666055561 in words is "three trillion, two hundred five billion, six hundred sixty-six million, fifty-five thousand, five hundred sixty-one".