18994541 has 2 divisors, whose sum is σ = 18994542. Its totient is φ = 18994540.

The previous prime is 18994529. The next prime is 18994561. The reversal of 18994541 is 14549981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14853316 + 4141225 = 3854^2 + 2035^2 .

It is an emirp because it is prime and its reverse (14549981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18994541 - 2⁶ = 18994477 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 (18994561) 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, 9497270 + 9497271.

It is an arithmetic number, because the mean of its divisors is an integer number (9497271).

Almost surely, 2^18994541 is an apocalyptic number.

It is an amenable number.

18994541 is a deficient number, since it is larger than the sum of its proper divisors (1).

18994541 is an equidigital number, since it uses as much as digits as its factorization.

18994541 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 41.

The square root of 18994541 is about 4358.2727083100. The cubic root of 18994541 is about 266.8146066267.

The spelling of 18994541 in words is "eighteen million, nine hundred ninety-four thousand, five hundred forty-one".