161481575767681 has 24 divisors (see below), whose sum is σ = 178582878696960. Its totient is φ = 145885379642496.

The previous prime is 161481575767679. The next prime is 161481575767769. The reversal of 161481575767681 is 186767575184161.

It is not a de Polignac number, because 161481575767681 - 2¹ = 161481575767679 is a prime.

It is a super-2 number, since 2×161481575767681² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161481575767181) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 436354381 + ... + 436724293.

It is an arithmetic number, because the mean of its divisors is an integer number (7440953279040).

Almost surely, 2^{161481575767681} is an apocalyptic number.

It is an amenable number.

161481575767681 is a deficient number, since it is larger than the sum of its proper divisors (17101302929279).

161481575767681 is a wasteful number, since it uses less digits than its factorization.

161481575767681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424945 (or 424932 counting only the distinct ones).

The product of its digits is 474163200, while the sum is 73.

The spelling of 161481575767681 in words is "one hundred sixty-one trillion, four hundred eighty-one billion, five hundred seventy-five million, seven hundred sixty-seven thousand, six hundred eighty-one".