161805323 has 2 divisors, whose sum is σ = 161805324. Its totient is φ = 161805322.

The previous prime is 161805289. The next prime is 161805361. The reversal of 161805323 is 323508161.

It is a weak prime.

It is an emirp because it is prime and its reverse (323508161) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161805323 is a prime.

It is a super-2 number, since 2×161805323² = 52361925102268658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161805223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80902661 + 80902662.

It is an arithmetic number, because the mean of its divisors is an integer number (80902662).

Almost surely, 2^161805323 is an apocalyptic number.

161805323 is a deficient number, since it is larger than the sum of its proper divisors (1).

161805323 is an equidigital number, since it uses as much as digits as its factorization.

161805323 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 161805323 is about 12720.2721275922. The cubic root of 161805323 is about 544.9177251443.

The spelling of 161805323 in words is "one hundred sixty-one million, eight hundred five thousand, three hundred twenty-three".