161243645866 has 8 divisors (see below), whose sum is σ = 241876926720. Its totient is φ = 80618003628.

The previous prime is 161243645789. The next prime is 161243645869. The reversal of 161243645866 is 668546342161.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (161243645869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1856586 + ... + 1941493.

It is an arithmetic number, because the mean of its divisors is an integer number (30234615840).

Almost surely, 2^161243645866 is an apocalyptic number.

161243645866 is a deficient number, since it is larger than the sum of its proper divisors (80633280854).

161243645866 is a wasteful number, since it uses less digits than its factorization.

161243645866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3819308.

The product of its digits is 4976640, while the sum is 52.

The spelling of 161243645866 in words is "one hundred sixty-one billion, two hundred forty-three million, six hundred forty-five thousand, eight hundred sixty-six".