161803422218 has 4 divisors (see below), whose sum is σ = 242705133330. Its totient is φ = 80901711108.

The previous prime is 161803422199. The next prime is 161803422241. The reversal of 161803422218 is 812224308161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 125544788329 + 36258633889 = 354323^2 + 190417^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40450855553 + ... + 40450855556.

Almost surely, 2^161803422218 is an apocalyptic number.

161803422218 is a deficient number, since it is larger than the sum of its proper divisors (80901711112).

161803422218 is an equidigital number, since it uses as much as digits as its factorization.

161803422218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80901711111.

The product of its (nonzero) digits is 36864, while the sum is 38.

The spelling of 161803422218 in words is "one hundred sixty-one billion, eight hundred three million, four hundred twenty-two thousand, two hundred eighteen".