17998081 has 2 divisors, whose sum is σ = 17998082. Its totient is φ = 17998080.

The previous prime is 17998069. The next prime is 17998093. The reversal of 17998081 is 18089971.

It is a balanced prime because it is at equal distance from previous prime (17998069) and next prime (17998093).

It can be written as a sum of positive squares in only one way, i.e., 17850625 + 147456 = 4225^2 + 384^2 .

It is a cyclic number.

It is not a de Polignac number, because 17998081 - 2⁷ = 17997953 is a prime.

It is a super-2 number, since 2×17998081² = 647861839365122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (17998181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8999040 + 8999041.

It is an arithmetic number, because the mean of its divisors is an integer number (8999041).

Almost surely, 2^17998081 is an apocalyptic number.

It is an amenable number.

17998081 is a deficient number, since it is larger than the sum of its proper divisors (1).

17998081 is an equidigital number, since it uses as much as digits as its factorization.

17998081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 17998081 is about 4242.4145247724. The cubic root of 17998081 is about 262.0648257515.

The spelling of 17998081 in words is "seventeen million, nine hundred ninety-eight thousand, eighty-one".