161561065111166 has 16 divisors (see below), whose sum is σ = 276962025566304. Its totient is φ = 69240406560864.

The previous prime is 161561065111139. The next prime is 161561065111169. The reversal of 161561065111166 is 661111560165161.

It is a super-2 number, since 2×161561065111166² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161561065111166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161561065111169) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21347816 + ... + 27907908.

It is an arithmetic number, because the mean of its divisors is an integer number (17310126597894).

Almost surely, 2^{161561065111166} is an apocalyptic number.

161561065111166 is a deficient number, since it is larger than the sum of its proper divisors (115400960455138).

161561065111166 is a wasteful number, since it uses less digits than its factorization.

161561065111166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8319235.

The product of its (nonzero) digits is 194400, while the sum is 47.

The spelling of 161561065111166 in words is "one hundred sixty-one trillion, five hundred sixty-one billion, sixty-five million, one hundred eleven thousand, one hundred sixty-six".