18840553 has 2 divisors, whose sum is σ = 18840554. Its totient is φ = 18840552.

The previous prime is 18840527. The next prime is 18840557. The reversal of 18840553 is 35504881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12475024 + 6365529 = 3532^2 + 2523^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18840553 is a prime.

It is not a weakly prime, because it can be changed into another prime (18840557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9420276 + 9420277.

It is an arithmetic number, because the mean of its divisors is an integer number (9420277).

Almost surely, 2^18840553 is an apocalyptic number.

It is an amenable number.

18840553 is a deficient number, since it is larger than the sum of its proper divisors (1).

18840553 is an equidigital number, since it uses as much as digits as its factorization.

18840553 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 18840553 is about 4340.5705846121. The cubic root of 18840553 is about 266.0916308584.

The spelling of 18840553 in words is "eighteen million, eight hundred forty thousand, five hundred fifty-three".