18191039 has 2 divisors, whose sum is σ = 18191040. Its totient is φ = 18191038.

The previous prime is 18191029. The next prime is 18191077. The reversal of 18191039 is 93019181.

It is a weak prime.

It is an emirp because it is prime and its reverse (93019181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18191039 - 2⁴ = 18191023 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18190996 and 18191014.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18191029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9095519 + 9095520.

It is an arithmetic number, because the mean of its divisors is an integer number (9095520).

Almost surely, 2^18191039 is an apocalyptic number.

18191039 is a deficient number, since it is larger than the sum of its proper divisors (1).

18191039 is an equidigital number, since it uses as much as digits as its factorization.

18191039 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 32.

The square root of 18191039 is about 4265.0954268340. The cubic root of 18191039 is about 262.9980337866.

The spelling of 18191039 in words is "eighteen million, one hundred ninety-one thousand, thirty-nine".