161565545411 has 2 divisors, whose sum is σ = 161565545412. Its totient is φ = 161565545410.

The previous prime is 161565545389. The next prime is 161565545461. The reversal of 161565545411 is 114545565161.

It is a happy number.

161565545411 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161565545411 is a prime.

It is a super-2 number, since 2×161565545411² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161565545461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80782772705 + 80782772706.

It is an arithmetic number, because the mean of its divisors is an integer number (80782772706).

Almost surely, 2^161565545411 is an apocalyptic number.

161565545411 is a deficient number, since it is larger than the sum of its proper divisors (1).

161565545411 is an equidigital number, since it uses as much as digits as its factorization.

161565545411 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 360000, while the sum is 44.

The spelling of 161565545411 in words is "one hundred sixty-one billion, five hundred sixty-five million, five hundred forty-five thousand, four hundred eleven".