161822241866 has 4 divisors (see below), whose sum is σ = 242733362802. Its totient is φ = 80911120932.

The previous prime is 161822241829. The next prime is 161822241869. The reversal of 161822241866 is 668142228161.

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., 160164042025 + 1658199841 = 400205^2 + 40721^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 161822241866.

It is not an unprimeable number, because it can be changed into a prime (161822241869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40455560465 + ... + 40455560468.

Almost surely, 2^161822241866 is an apocalyptic number.

161822241866 is a deficient number, since it is larger than the sum of its proper divisors (80911120936).

161822241866 is an equidigital number, since it uses as much as digits as its factorization.

161822241866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80911120935.

The product of its digits is 442368, while the sum is 47.

The spelling of 161822241866 in words is "one hundred sixty-one billion, eight hundred twenty-two million, two hundred forty-one thousand, eight hundred sixty-six".