181313329 has 2 divisors, whose sum is σ = 181313330. Its totient is φ = 181313328.

The previous prime is 181313291. The next prime is 181313351. The reversal of 181313329 is 923313181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 132871729 + 48441600 = 11527^2 + 6960^2 .

It is a cyclic number.

It is not a de Polignac number, because 181313329 - 2¹⁷ = 181182257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181313329.

It is not a weakly prime, because it can be changed into another prime (181313729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90656664 + 90656665.

It is an arithmetic number, because the mean of its divisors is an integer number (90656665).

Almost surely, 2^181313329 is an apocalyptic number.

It is an amenable number.

181313329 is a deficient number, since it is larger than the sum of its proper divisors (1).

181313329 is an equidigital number, since it uses as much as digits as its factorization.

181313329 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 31.

The square root of 181313329 is about 13465.2637924402. The cubic root of 181313329 is about 565.9915020346.

The spelling of 181313329 in words is "one hundred eighty-one million, three hundred thirteen thousand, three hundred twenty-nine".