18499139 has 2 divisors, whose sum is σ = 18499140. Its totient is φ = 18499138.

The previous prime is 18499133. The next prime is 18499181. The reversal of 18499139 is 93199481.

It is a weak prime.

It is an emirp because it is prime and its reverse (93199481) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18499139 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18499139.

It is not a weakly prime, because it can be changed into another prime (18499133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9249569 + 9249570.

It is an arithmetic number, because the mean of its divisors is an integer number (9249570).

Almost surely, 2^18499139 is an apocalyptic number.

18499139 is a deficient number, since it is larger than the sum of its proper divisors (1).

18499139 is an equidigital number, since it uses as much as digits as its factorization.

18499139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69984, while the sum is 44.

The square root of 18499139 is about 4301.0625431398. The cubic root of 18499139 is about 264.4745205784.

The spelling of 18499139 in words is "eighteen million, four hundred ninety-nine thousand, one hundred thirty-nine".