161993289 has 16 divisors (see below), whose sum is σ = 234880128. Its totient is φ = 98894592.

The previous prime is 161993269. The next prime is 161993311. The reversal of 161993289 is 982399161.

161993289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 161993289 - 2²³ = 153604681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161993239) 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, 41037 + ... + 44810.

It is an arithmetic number, because the mean of its divisors is an integer number (14680008).

Almost surely, 2^161993289 is an apocalyptic number.

It is an amenable number.

161993289 is a deficient number, since it is larger than the sum of its proper divisors (72886839).

161993289 is a wasteful number, since it uses less digits than its factorization.

161993289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85904.

The product of its digits is 209952, while the sum is 48.

The square root of 161993289 is about 12727.6584256492. The cubic root of 161993289 is about 545.1286501554.

The spelling of 161993289 in words is "one hundred sixty-one million, nine hundred ninety-three thousand, two hundred eighty-nine".