161966216 has 8 divisors (see below), whose sum is σ = 303686670. Its totient is φ = 80983104.

The previous prime is 161966209. The next prime is 161966249. The reversal of 161966216 is 612669161.

It can be written as a sum of positive squares in only one way, i.e., 159921316 + 2044900 = 12646^2 + 1430^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 161966216.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10122881 + ... + 10122896.

Almost surely, 2^161966216 is an apocalyptic number.

It is an amenable number.

161966216 is a deficient number, since it is larger than the sum of its proper divisors (141720454).

161966216 is a wasteful number, since it uses less digits than its factorization.

161966216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20245783 (or 20245779 counting only the distinct ones).

The product of its digits is 23328, while the sum is 38.

The square root of 161966216 is about 12726.5948312972. The cubic root of 161966216 is about 545.0982803990.

The spelling of 161966216 in words is "one hundred sixty-one million, nine hundred sixty-six thousand, two hundred sixteen".