80661181 has 2 divisors, whose sum is σ = 80661182. Its totient is φ = 80661180.

The previous prime is 80661157. The next prime is 80661187. The reversal of 80661181 is 18116608.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 69572281 + 11088900 = 8341^2 + 3330^2 .

It is a cyclic number.

It is not a de Polignac number, because 80661181 - 2¹³ = 80652989 is a prime.

It is a super-2 number, since 2×80661181² = 13012452240629522, which contains 22 as substring.

It is equal to p_4705726 and since 80661181 and 4705726 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80661187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40330590 + 40330591.

It is an arithmetic number, because the mean of its divisors is an integer number (40330591).

Almost surely, 2^80661181 is an apocalyptic number.

It is an amenable number.

80661181 is a deficient number, since it is larger than the sum of its proper divisors (1).

80661181 is an equidigital number, since it uses as much as digits as its factorization.

80661181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 80661181 is about 8981.1569967349. The cubic root of 80661181 is about 432.0707420873.

Adding to 80661181 its reverse (18116608), we get a palindrome (98777789).

The spelling of 80661181 in words is "eighty million, six hundred sixty-one thousand, one hundred eighty-one".