1109843720161 has 16 divisors (see below), whose sum is σ = 1252548123840. Its totient is φ = 974110898880.

The previous prime is 1109843720143. The next prime is 1109843720171. The reversal of 1109843720161 is 1610273489011.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1109843720161 - 2²⁵ = 1109810165729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1109843720171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7749970 + ... + 7891876.

It is an arithmetic number, because the mean of its divisors is an integer number (78284257740).

Almost surely, 2^{1109843720161} is an apocalyptic number.

1109843720161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1109843720161 is a deficient number, since it is larger than the sum of its proper divisors (142704403679).

1109843720161 is a wasteful number, since it uses less digits than its factorization.

1109843720161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166464.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 1109843720161 in words is "one trillion, one hundred nine billion, eight hundred forty-three million, seven hundred twenty thousand, one hundred sixty-one".