161322811 has 8 divisors (see below), whose sum is σ = 173999840. Its totient is φ = 148684032.

The previous prime is 161322803. The next prime is 161322827. The reversal of 161322811 is 118223161.

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 161322811 - 2³ = 161322803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161322871) 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 7 ways as a sum of consecutive naturals, for example, 471 + ... + 17968.

It is an arithmetic number, because the mean of its divisors is an integer number (21749980).

Almost surely, 2^161322811 is an apocalyptic number.

161322811 is a deficient number, since it is larger than the sum of its proper divisors (12677029).

161322811 is a wasteful number, since it uses less digits than its factorization.

161322811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19125.

The product of its digits is 576, while the sum is 25.

The square root of 161322811 is about 12701.2917059644. The cubic root of 161322811 is about 544.3755280424.

Adding to 161322811 its reverse (118223161), we get a palindrome (279545972).

The spelling of 161322811 in words is "one hundred sixty-one million, three hundred twenty-two thousand, eight hundred eleven".