111611661161 has 64 divisors (see below), whose sum is σ = 162362382336. Its totient is φ = 73800115200.

The previous prime is 111611661131. The next prime is 111611661167. The reversal of 111611661161 is 161166116111.

It is not a de Polignac number, because 111611661161 - 2²⁶ = 111544552297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (111611661167) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 655466 + ... + 807996.

It is an arithmetic number, because the mean of its divisors is an integer number (2536912224).

Almost surely, 2^111611661161 is an apocalyptic number.

111611661161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111611661161 is a deficient number, since it is larger than the sum of its proper divisors (50750721175).

111611661161 is a wasteful number, since it uses less digits than its factorization.

111611661161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152622.

The product of its digits is 1296, while the sum is 32.

Adding to 111611661161 its reverse (161166116111), we get a palindrome (272777777272).

The spelling of 111611661161 in words is "one hundred eleven billion, six hundred eleven million, six hundred sixty-one thousand, one hundred sixty-one".