181333743889 has 27 divisors (see below), whose sum is σ = 198267614643. Its totient is φ = 165809150208.

The previous prime is 181333743887. The next prime is 181333743893. The reversal of 181333743889 is 988347333181.

It is a happy number.

The square root of 181333743889 is 425833.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 70572579025 + 110761164864 = 265655^2 + 332808^2 .

It is not a de Polignac number, because 181333743889 - 2¹ = 181333743887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (181333743887) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 267848619 + ... + 267849295.

Almost surely, 2^181333743889 is an apocalyptic number.

181333743889 is the 425833-rd square number.

181333743889 is the 212917-th centered octagonal number.

It is an amenable number.

181333743889 is a deficient number, since it is larger than the sum of its proper divisors (16933870754).

181333743889 is an frugal number, since it uses more digits than its factorization.

181333743889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1462 (or 731 counting only the distinct ones).

The product of its digits is 10450944, while the sum is 58.

The spelling of 181333743889 in words is "one hundred eighty-one billion, three hundred thirty-three million, seven hundred forty-three thousand, eight hundred eighty-nine".