181000993 has 2 divisors, whose sum is σ = 181000994. Its totient is φ = 181000992.

The previous prime is 181000949. The next prime is 181001021. The reversal of 181000993 is 399000181.

181000993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 172975104 + 8025889 = 13152^2 + 2833^2 .

It is an emirp because it is prime and its reverse (399000181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 181000993 - 2²¹ = 178903841 is a prime.

It is a super-2 number, since 2×181000993² = 65522718933972098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (181000903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90500496 + 90500497.

It is an arithmetic number, because the mean of its divisors is an integer number (90500497).

Almost surely, 2^181000993 is an apocalyptic number.

It is an amenable number.

181000993 is a deficient number, since it is larger than the sum of its proper divisors (1).

181000993 is an equidigital number, since it uses as much as digits as its factorization.

181000993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 181000993 is about 13453.6609515775. The cubic root of 181000993 is about 565.6663170291. Note that the first 3 decimals are identical.

The spelling of 181000993 in words is "one hundred eighty-one million, nine hundred ninety-three", and thus it is an aban number.