161611100500111 has 4 divisors (see below), whose sum is σ = 163426955562000. Its totient is φ = 159795245438224.

The previous prime is 161611100500067. The next prime is 161611100500153. The reversal of 161611100500111 is 111005001116161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161611100500111 - 2¹⁷ = 161611100369039 is a prime.

It is a super-2 number, since 2×161611100500111² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161611100500711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 907927530811 + ... + 907927530988.

It is an arithmetic number, because the mean of its divisors is an integer number (40856738890500).

Almost surely, 2^{161611100500111} is an apocalyptic number.

161611100500111 is a deficient number, since it is larger than the sum of its proper divisors (1815855061889).

161611100500111 is an equidigital number, since it uses as much as digits as its factorization.

161611100500111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1815855061888.

The product of its (nonzero) digits is 180, while the sum is 25.

Adding to 161611100500111 its reverse (111005001116161), we get a palindrome (272616101616272).

The spelling of 161611100500111 in words is "one hundred sixty-one trillion, six hundred eleven billion, one hundred million, five hundred thousand, one hundred eleven".