161565505411 has 2 divisors, whose sum is σ = 161565505412. Its totient is φ = 161565505410.

The previous prime is 161565505391. The next prime is 161565505427. The reversal of 161565505411 is 114505565161.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161565505411 - 2⁵ = 161565505379 is a prime.

It is a super-2 number, since 2×161565505411² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161565545411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80782752705 + 80782752706.

It is an arithmetic number, because the mean of its divisors is an integer number (80782752706).

Almost surely, 2^161565505411 is an apocalyptic number.

161565505411 is a deficient number, since it is larger than the sum of its proper divisors (1).

161565505411 is an equidigital number, since it uses as much as digits as its factorization.

161565505411 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 90000, while the sum is 40.

The spelling of 161565505411 in words is "one hundred sixty-one billion, five hundred sixty-five million, five hundred five thousand, four hundred eleven".