18539113 has 2 divisors, whose sum is σ = 18539114. Its totient is φ = 18539112.

The previous prime is 18539099. The next prime is 18539123. The reversal of 18539113 is 31193581.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16096144 + 2442969 = 4012^2 + 1563^2 .

It is an emirp because it is prime and its reverse (31193581) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18539113 - 2²¹ = 16441961 is a prime.

It is not a weakly prime, because it can be changed into another prime (18539123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9269556 + 9269557.

It is an arithmetic number, because the mean of its divisors is an integer number (9269557).

Almost surely, 2^18539113 is an apocalyptic number.

It is an amenable number.

18539113 is a deficient number, since it is larger than the sum of its proper divisors (1).

18539113 is an equidigital number, since it uses as much as digits as its factorization.

18539113 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3240, while the sum is 31.

The square root of 18539113 is about 4305.7070267263. The cubic root of 18539113 is about 264.6648807653.

The spelling of 18539113 in words is "eighteen million, five hundred thirty-nine thousand, one hundred thirteen".