161845643 has 2 divisors, whose sum is σ = 161845644. Its totient is φ = 161845642.

The previous prime is 161845639. The next prime is 161845657. The reversal of 161845643 is 346548161.

It is a weak prime.

It is an emirp because it is prime and its reverse (346548161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161845643 - 2² = 161845639 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 161845597 and 161845606.

It is not a weakly prime, because it can be changed into another prime (161845633) 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, 80922821 + 80922822.

It is an arithmetic number, because the mean of its divisors is an integer number (80922822).

Almost surely, 2^161845643 is an apocalyptic number.

161845643 is a deficient number, since it is larger than the sum of its proper divisors (1).

161845643 is an equidigital number, since it uses as much as digits as its factorization.

161845643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 38.

The square root of 161845643 is about 12721.8569006258. The cubic root of 161845643 is about 544.9629837665.

The spelling of 161845643 in words is "one hundred sixty-one million, eight hundred forty-five thousand, six hundred forty-three".