111261161 has 4 divisors (see below), whose sum is σ = 121375824. Its totient is φ = 101146500.

The previous prime is 111261149. The next prime is 111261181. The reversal of 111261161 is 161162111.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 111261161 - 2¹⁰ = 111260137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111261121) 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, 5057315 + ... + 5057336.

It is an arithmetic number, because the mean of its divisors is an integer number (30343956).

Almost surely, 2^111261161 is an apocalyptic number.

111261161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

111261161 is a deficient number, since it is larger than the sum of its proper divisors (10114663).

111261161 is a wasteful number, since it uses less digits than its factorization.

111261161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10114662.

The product of its digits is 72, while the sum is 20.

The square root of 111261161 is about 10548.0406237367. The cubic root of 111261161 is about 480.9661688133.

The spelling of 111261161 in words is "one hundred eleven million, two hundred sixty-one thousand, one hundred sixty-one".