18818573 has 2 divisors, whose sum is σ = 18818574. Its totient is φ = 18818572.

The previous prime is 18818567. The next prime is 18818587. The reversal of 18818573 is 37581881.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18550249 + 268324 = 4307^2 + 518^2 .

It is a cyclic number.

It is not a de Polignac number, because 18818573 - 2¹⁶ = 18753037 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18818573.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18818773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9409286 + 9409287.

It is an arithmetic number, because the mean of its divisors is an integer number (9409287).

Almost surely, 2^18818573 is an apocalyptic number.

It is an amenable number.

18818573 is a deficient number, since it is larger than the sum of its proper divisors (1).

18818573 is an equidigital number, since it uses as much as digits as its factorization.

18818573 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 41.

The square root of 18818573 is about 4338.0379205350. The cubic root of 18818573 is about 265.9881135510.

It can be divided in two parts, 18818 and 573, that added together give a palindrome (19391).

The spelling of 18818573 in words is "eighteen million, eight hundred eighteen thousand, five hundred seventy-three".