8181361 has 2 divisors, whose sum is σ = 8181362. Its totient is φ = 8181360.

The previous prime is 8181359. The next prime is 8181377. The reversal of 8181361 is 1631818.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8088336 + 93025 = 2844^2 + 305^2 .

It is a cyclic number.

It is not a de Polignac number, because 8181361 - 2¹ = 8181359 is a prime.

Together with 8181359, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8181311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4090680 + 4090681.

It is an arithmetic number, because the mean of its divisors is an integer number (4090681).

Almost surely, 2^8181361 is an apocalyptic number.

It is an amenable number.

8181361 is a deficient number, since it is larger than the sum of its proper divisors (1).

8181361 is an equidigital number, since it uses as much as digits as its factorization.

8181361 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 28.

The square root of 8181361 is about 2860.3078505643. The cubic root of 8181361 is about 201.5000625991.

The spelling of 8181361 in words is "eight million, one hundred eighty-one thousand, three hundred sixty-one".