161908289 has 8 divisors (see below), whose sum is σ = 171906048. Its totient is φ = 151963200.

The previous prime is 161908283. The next prime is 161908309. The reversal of 161908289 is 982809161.

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-161908289 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161908283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6737 + ... + 19214.

It is an arithmetic number, because the mean of its divisors is an integer number (21488256).

Almost surely, 2^161908289 is an apocalyptic number.

It is an amenable number.

161908289 is a deficient number, since it is larger than the sum of its proper divisors (9997759).

161908289 is a wasteful number, since it uses less digits than its factorization.

161908289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26335.

The product of its (nonzero) digits is 62208, while the sum is 44.

The square root of 161908289 is about 12724.3188029851. The cubic root of 161908289 is about 545.0332880938.

The spelling of 161908289 in words is "one hundred sixty-one million, nine hundred eight thousand, two hundred eighty-nine".