161140906181 has 2 divisors, whose sum is σ = 161140906182. Its totient is φ = 161140906180.

The previous prime is 161140906097. The next prime is 161140906189. The reversal of 161140906181 is 181609041161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111963852100 + 49177054081 = 334610^2 + 221759^2 .

It is an emirp because it is prime and its reverse (181609041161) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161140906181 is a prime.

It is a super-2 number, since 2×161140906181² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161140906189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80570453090 + 80570453091.

It is an arithmetic number, because the mean of its divisors is an integer number (80570453091).

Almost surely, 2^161140906181 is an apocalyptic number.

It is an amenable number.

161140906181 is a deficient number, since it is larger than the sum of its proper divisors (1).

161140906181 is an equidigital number, since it uses as much as digits as its factorization.

161140906181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 38.

The spelling of 161140906181 in words is "one hundred sixty-one billion, one hundred forty million, nine hundred six thousand, one hundred eighty-one".