18820433 has 2 divisors, whose sum is σ = 18820434. Its totient is φ = 18820432.

The previous prime is 18820429. The next prime is 18820453. The reversal of 18820433 is 33402881.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14227984 + 4592449 = 3772^2 + 2143^2 .

It is an emirp because it is prime and its reverse (33402881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18820433 - 2² = 18820429 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18820396 and 18820405.

It is not a weakly prime, because it can be changed into another prime (18820453) 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, 9410216 + 9410217.

It is an arithmetic number, because the mean of its divisors is an integer number (9410217).

Almost surely, 2^18820433 is an apocalyptic number.

It is an amenable number.

18820433 is a deficient number, since it is larger than the sum of its proper divisors (1).

18820433 is an equidigital number, since it uses as much as digits as its factorization.

18820433 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 18820433 is about 4338.2522978730. The cubic root of 18820433 is about 265.9968765533.

The spelling of 18820433 in words is "eighteen million, eight hundred twenty thousand, four hundred thirty-three".