18889517 has 2 divisors, whose sum is σ = 18889518. Its totient is φ = 18889516.

The previous prime is 18889487. The next prime is 18889531. The reversal of 18889517 is 71598881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16760836 + 2128681 = 4094^2 + 1459^2 .

It is an emirp because it is prime and its reverse (71598881) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18889517 - 2¹² = 18885421 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18889217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9444758 + 9444759.

It is an arithmetic number, because the mean of its divisors is an integer number (9444759).

Almost surely, 2^18889517 is an apocalyptic number.

It is an amenable number.

18889517 is a deficient number, since it is larger than the sum of its proper divisors (1).

18889517 is an equidigital number, since it uses as much as digits as its factorization.

18889517 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 47.

The square root of 18889517 is about 4346.2071970858. The cubic root of 18889517 is about 266.3219432790.

The spelling of 18889517 in words is "eighteen million, eight hundred eighty-nine thousand, five hundred seventeen".