161322909 has 16 divisors (see below), whose sum is σ = 235669824. Its totient is φ = 97347200.

The previous prime is 161322907. The next prime is 161322929. The reversal of 161322909 is 909223161.

It is a cyclic number.

It is not a de Polignac number, because 161322909 - 2¹ = 161322907 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a self number, because there is not a number n which added to its sum of digits gives 161322909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161322907) 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, 2802 + ... + 18179.

It is an arithmetic number, because the mean of its divisors is an integer number (14729364).

Almost surely, 2^161322909 is an apocalyptic number.

It is an amenable number.

161322909 is a deficient number, since it is larger than the sum of its proper divisors (74346915).

161322909 is a wasteful number, since it uses less digits than its factorization.

161322909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21228.

The product of its (nonzero) digits is 5832, while the sum is 33.

The square root of 161322909 is about 12701.2955638391. The cubic root of 161322909 is about 544.3756382744.

The spelling of 161322909 in words is "one hundred sixty-one million, three hundred twenty-two thousand, nine hundred nine".