72186161 has 2 divisors, whose sum is σ = 72186162. Its totient is φ = 72186160.

The previous prime is 72186157. The next prime is 72186173. The reversal of 72186161 is 16168127.

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., 64705936 + 7480225 = 8044^2 + 2735^2 .

It is a cyclic number.

It is not a de Polignac number, because 72186161 - 2² = 72186157 is a prime.

It is not a weakly prime, because it can be changed into another prime (72186761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36093080 + 36093081.

It is an arithmetic number, because the mean of its divisors is an integer number (36093081).

Almost surely, 2^72186161 is an apocalyptic number.

It is an amenable number.

72186161 is a deficient number, since it is larger than the sum of its proper divisors (1).

72186161 is an equidigital number, since it uses as much as digits as its factorization.

72186161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 32.

The square root of 72186161 is about 8496.2439348220. The cubic root of 72186161 is about 416.3750027826.

The spelling of 72186161 in words is "seventy-two million, one hundred eighty-six thousand, one hundred sixty-one".