72220317082181 has 2 divisors, whose sum is σ = 72220317082182. Its totient is φ = 72220317082180.

The previous prime is 72220317082169. The next prime is 72220317082241. The reversal of 72220317082181 is 18128071302227.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44761050736900 + 27459266345281 = 6690370^2 + 5240159^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72220317082181 is a prime.

It is a super-2 number, since 2×72220317082181² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72220317085181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36110158541090 + 36110158541091.

It is an arithmetic number, because the mean of its divisors is an integer number (36110158541091).

Almost surely, 2^{72220317082181} is an apocalyptic number.

It is an amenable number.

72220317082181 is a deficient number, since it is larger than the sum of its proper divisors (1).

72220317082181 is an equidigital number, since it uses as much as digits as its factorization.

72220317082181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 150528, while the sum is 44.

The spelling of 72220317082181 in words is "seventy-two trillion, two hundred twenty billion, three hundred seventeen million, eighty-two thousand, one hundred eighty-one".