186881161 has 2 divisors, whose sum is σ = 186881162. Its totient is φ = 186881160.

The previous prime is 186881129. The next prime is 186881173. The reversal of 186881161 is 161188681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116640000 + 70241161 = 10800^2 + 8381^2 .

It is an emirp because it is prime and its reverse (161188681) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 191188981 and 189881191.

It is a cyclic number.

It is not a de Polignac number, because 186881161 - 2⁵ = 186881129 is a prime.

It is not a weakly prime, because it can be changed into another prime (186882161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93440580 + 93440581.

It is an arithmetic number, because the mean of its divisors is an integer number (93440581).

Almost surely, 2^186881161 is an apocalyptic number.

It is an amenable number.

186881161 is a deficient number, since it is larger than the sum of its proper divisors (1).

186881161 is an equidigital number, since it uses as much as digits as its factorization.

186881161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18432, while the sum is 40.

The square root of 186881161 is about 13670.4484564333. The cubic root of 186881161 is about 571.7267438593.

The spelling of 186881161 in words is "one hundred eighty-six million, eight hundred eighty-one thousand, one hundred sixty-one".