161911611 has 12 divisors (see below), whose sum is σ = 241937280. Its totient is φ = 104218800.

The previous prime is 161911601. The next prime is 161911613. The reversal of 161911611 is 116119161.

It is not a de Polignac number, because 161911611 - 2¹³ = 161903419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161911613) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 309915 + ... + 310436.

It is an arithmetic number, because the mean of its divisors is an integer number (20161440).

Almost surely, 2^161911611 is an apocalyptic number.

161911611 is a deficient number, since it is larger than the sum of its proper divisors (80025669).

161911611 is a wasteful number, since it uses less digits than its factorization.

161911611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620386 (or 620383 counting only the distinct ones).

The product of its digits is 324, while the sum is 27.

The square root of 161911611 is about 12724.4493397553. The cubic root of 161911611 is about 545.0370156942.

The spelling of 161911611 in words is "one hundred sixty-one million, nine hundred eleven thousand, six hundred eleven".