17998973 has 2 divisors, whose sum is σ = 17998974. Its totient is φ = 17998972.

The previous prime is 17998963. The next prime is 17998993. The reversal of 17998973 is 37989971.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17623204 + 375769 = 4198^2 + 613^2 .

It is a cyclic number.

It is not a de Polignac number, because 17998973 - 2⁴ = 17998957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17998963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8999486 + 8999487.

It is an arithmetic number, because the mean of its divisors is an integer number (8999487).

Almost surely, 2^17998973 is an apocalyptic number.

It is an amenable number.

17998973 is a deficient number, since it is larger than the sum of its proper divisors (1).

17998973 is an equidigital number, since it uses as much as digits as its factorization.

17998973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 857304, while the sum is 53.

The square root of 17998973 is about 4242.5196522821. The cubic root of 17998973 is about 262.0691550642.

The spelling of 17998973 in words is "seventeen million, nine hundred ninety-eight thousand, nine hundred seventy-three".