8161192681 has 2 divisors, whose sum is σ = 8161192682. Its totient is φ = 8161192680.

The previous prime is 8161192667. The next prime is 8161192687. The reversal of 8161192681 is 1862911618.

8161192681 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4475610000 + 3685582681 = 66900^2 + 60709^2 .

It is a cyclic number.

It is not a de Polignac number, because 8161192681 - 2¹⁷ = 8161061609 is a prime.

It is a super-2 number, since 2×8161192681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8161192687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4080596340 + 4080596341.

It is an arithmetic number, because the mean of its divisors is an integer number (4080596341).

Almost surely, 2^8161192681 is an apocalyptic number.

It is an amenable number.

8161192681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8161192681 is an equidigital number, since it uses as much as digits as its factorization.

8161192681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 43.

The square root of 8161192681 is about 90339.3196841774. The cubic root of 8161192681 is about 2013.3435009251.

The spelling of 8161192681 in words is "eight billion, one hundred sixty-one million, one hundred ninety-two thousand, six hundred eighty-one".