161200803681 has 6 divisors (see below), whose sum is σ = 232845605330. Its totient is φ = 107467202448.

The previous prime is 161200803677. The next prime is 161200803683. The reversal of 161200803681 is 186308002161.

161200803681 is a `hidden beast` number, since 1 + 612 + 0 + 0 + 8 + 0 + 36 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 154147323456 + 7053480225 = 392616^2 + 83985^2 .

It is not a de Polignac number, because 161200803681 - 2² = 161200803677 is a prime.

It is a super-2 number, since 2×161200803681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161200803683) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8955600196 + ... + 8955600213.

Almost surely, 2^161200803681 is an apocalyptic number.

It is an amenable number.

161200803681 is a deficient number, since it is larger than the sum of its proper divisors (71644801649).

161200803681 is a wasteful number, since it uses less digits than its factorization.

161200803681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17911200415 (or 17911200412 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The spelling of 161200803681 in words is "one hundred sixty-one billion, two hundred million, eight hundred three thousand, six hundred eighty-one".