161943416815 has 4 divisors (see below), whose sum is σ = 194332100184. Its totient is φ = 129554733448.

The previous prime is 161943416731. The next prime is 161943416819. The reversal of 161943416815 is 518614349161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 518614349161 = 343997 ⋅1507613.

It is a cyclic number.

It is not a de Polignac number, because 161943416815 - 2¹¹ = 161943414767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161943416819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16194341677 + ... + 16194341686.

It is an arithmetic number, because the mean of its divisors is an integer number (48583025046).

Almost surely, 2^161943416815 is an apocalyptic number.

161943416815 is a deficient number, since it is larger than the sum of its proper divisors (32388683369).

161943416815 is an equidigital number, since it uses as much as digits as its factorization.

161943416815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32388683368.

The product of its digits is 622080, while the sum is 49.

The spelling of 161943416815 in words is "one hundred sixty-one billion, nine hundred forty-three million, four hundred sixteen thousand, eight hundred fifteen".