161331611 has 16 divisors (see below), whose sum is σ = 192162240. Its totient is φ = 132518400.

The previous prime is 161331607. The next prime is 161331631. The reversal of 161331611 is 116133161.

It is not a de Polignac number, because 161331611 - 2² = 161331607 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161331631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24911 + ... + 30711.

It is an arithmetic number, because the mean of its divisors is an integer number (12010140).

Almost surely, 2^161331611 is an apocalyptic number.

161331611 is a deficient number, since it is larger than the sum of its proper divisors (30830629).

161331611 is a wasteful number, since it uses less digits than its factorization.

161331611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5974.

The product of its digits is 324, while the sum is 23.

The square root of 161331611 is about 12701.6381226990. The cubic root of 161331611 is about 544.3854262449.

Adding to 161331611 its reverse (116133161), we get a palindrome (277464772).

The spelling of 161331611 in words is "one hundred sixty-one million, three hundred thirty-one thousand, six hundred eleven".