181641533 has 2 divisors, whose sum is σ = 181641534. Its totient is φ = 181641532.

The previous prime is 181641517. The next prime is 181641571. The reversal of 181641533 is 335146181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 148888804 + 32752729 = 12202^2 + 5723^2 .

It is an emirp because it is prime and its reverse (335146181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181641533 - 2⁴ = 181641517 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 181641533.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (181641233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90820766 + 90820767.

It is an arithmetic number, because the mean of its divisors is an integer number (90820767).

Almost surely, 2^181641533 is an apocalyptic number.

It is an amenable number.

181641533 is a deficient number, since it is larger than the sum of its proper divisors (1).

181641533 is an equidigital number, since it uses as much as digits as its factorization.

181641533 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8640, while the sum is 32.

The square root of 181641533 is about 13477.4453439812. The cubic root of 181641533 is about 566.3328056842.

The spelling of 181641533 in words is "one hundred eighty-one million, six hundred forty-one thousand, five hundred thirty-three".