181144723381 has 2 divisors, whose sum is σ = 181144723382. Its totient is φ = 181144723380.

The previous prime is 181144723373. The next prime is 181144723393. The reversal of 181144723381 is 183327441181.

181144723381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 180489875281 + 654848100 = 424841^2 + 25590^2 .

It is an emirp because it is prime and its reverse (183327441181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181144723381 - 2³ = 181144723373 is a prime.

It is a super-2 number, since 2×181144723381² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181144726381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90572361690 + 90572361691.

It is an arithmetic number, because the mean of its divisors is an integer number (90572361691).

Almost surely, 2^181144723381 is an apocalyptic number.

It is an amenable number.

181144723381 is a deficient number, since it is larger than the sum of its proper divisors (1).

181144723381 is an equidigital number, since it uses as much as digits as its factorization.

181144723381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129024, while the sum is 43.

The spelling of 181144723381 in words is "one hundred eighty-one billion, one hundred forty-four million, seven hundred twenty-three thousand, three hundred eighty-one".