161409909 has 8 divisors (see below), whose sum is σ = 218244672. Its totient is φ = 106090880.

The previous prime is 161409893. The next prime is 161409943. The reversal of 161409909 is 909904161.

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

It is a cyclic number.

It is not a de Polignac number, because 161409909 - 2⁴ = 161409893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161409979) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 378684 + ... + 379109.

It is an arithmetic number, because the mean of its divisors is an integer number (27280584).

Almost surely, 2^161409909 is an apocalyptic number.

It is an amenable number.

161409909 is a deficient number, since it is larger than the sum of its proper divisors (56834763).

161409909 is an equidigital number, since it uses as much as digits as its factorization.

161409909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757867.

The product of its (nonzero) digits is 17496, while the sum is 39.

The square root of 161409909 is about 12704.7199496880. The cubic root of 161409909 is about 544.4734796569.

The spelling of 161409909 in words is "one hundred sixty-one million, four hundred nine thousand, nine hundred nine".