181000073 has 2 divisors, whose sum is σ = 181000074. Its totient is φ = 181000072.

The previous prime is 181000033. The next prime is 181000097. The reversal of 181000073 is 370000181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105431824 + 75568249 = 10268^2 + 8693^2 .

It is a cyclic number.

It is not a de Polignac number, because 181000073 - 2¹² = 180995977 is a prime.

It is a super-2 number, since 2×181000073² = 65522052852010658, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (181000033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90500036 + 90500037.

It is an arithmetic number, because the mean of its divisors is an integer number (90500037).

Almost surely, 2^181000073 is an apocalyptic number.

It is an amenable number.

181000073 is a deficient number, since it is larger than the sum of its proper divisors (1).

181000073 is an equidigital number, since it uses as much as digits as its factorization.

181000073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 20.

The square root of 181000073 is about 13453.6267600971. The cubic root of 181000073 is about 565.6653586294.

The spelling of 181000073 in words is "one hundred eighty-one million, seventy-three", and thus it is an aban number.