111621161 has 8 divisors (see below), whose sum is σ = 113986344. Its totient is φ = 109278720.

The previous prime is 111621131. The next prime is 111621187. The reversal of 111621161 is 161126111.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2544025 + 109077136 = 1595^2 + 10444^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111621161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111621131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4421 + ... + 15581.

It is an arithmetic number, because the mean of its divisors is an integer number (14248293).

Almost surely, 2^111621161 is an apocalyptic number.

It is an amenable number.

111621161 is a deficient number, since it is larger than the sum of its proper divisors (2365183).

111621161 is a wasteful number, since it uses less digits than its factorization.

111621161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11371.

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

The square root of 111621161 is about 10565.0916228871. The cubic root of 111621161 is about 481.4843532565.

Adding to 111621161 its reverse (161126111), we get a palindrome (272747272).

The spelling of 111621161 in words is "one hundred eleven million, six hundred twenty-one thousand, one hundred sixty-one".