8641537181 has 2 divisors, whose sum is σ = 8641537182. Its totient is φ = 8641537180.

The previous prime is 8641537141. The next prime is 8641537199. The reversal of 8641537181 is 1817351468.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8610912025 + 30625156 = 92795^2 + 5534^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8641537181 is a prime.

It is a super-2 number, since 2×8641537181² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8641537111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4320768590 + 4320768591.

It is an arithmetic number, because the mean of its divisors is an integer number (4320768591).

Almost surely, 2^8641537181 is an apocalyptic number.

It is an amenable number.

8641537181 is a deficient number, since it is larger than the sum of its proper divisors (1).

8641537181 is an equidigital number, since it uses as much as digits as its factorization.

8641537181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 161280, while the sum is 44.

The square root of 8641537181 is about 92959.8686584700. The cubic root of 8641537181 is about 2052.0928205799.

The spelling of 8641537181 in words is "eight billion, six hundred forty-one million, five hundred thirty-seven thousand, one hundred eighty-one".