18997073 has 2 divisors, whose sum is σ = 18997074. Its totient is φ = 18997072.

The previous prime is 18997061. The next prime is 18997087. The reversal of 18997073 is 37079981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18861649 + 135424 = 4343^2 + 368^2 .

It is a cyclic number.

It is not a de Polignac number, because 18997073 - 2¹⁰ = 18996049 is a prime.

It is not a weakly prime, because it can be changed into another prime (18997273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9498536 + 9498537.

It is an arithmetic number, because the mean of its divisors is an integer number (9498537).

Almost surely, 2^18997073 is an apocalyptic number.

It is an amenable number.

18997073 is a deficient number, since it is larger than the sum of its proper divisors (1).

18997073 is an equidigital number, since it uses as much as digits as its factorization.

18997073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 18997073 is about 4358.5631806824. The cubic root of 18997073 is about 266.8264616920.

The spelling of 18997073 in words is "eighteen million, nine hundred ninety-seven thousand, seventy-three".