18293939 has 2 divisors, whose sum is σ = 18293940. Its totient is φ = 18293938.

The previous prime is 18293927. The next prime is 18293971. The reversal of 18293939 is 93939281.

It is a weak prime.

It is an emirp because it is prime and its reverse (93939281) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18293939 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18293939.

It is not a weakly prime, because it can be changed into another prime (18293239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9146969 + 9146970.

It is an arithmetic number, because the mean of its divisors is an integer number (9146970).

Almost surely, 2^18293939 is an apocalyptic number.

18293939 is a deficient number, since it is larger than the sum of its proper divisors (1).

18293939 is an equidigital number, since it uses as much as digits as its factorization.

18293939 is an evil number, because the sum of its binary digits is even.

The product of its digits is 104976, while the sum is 44.

The square root of 18293939 is about 4277.1414519513. The cubic root of 18293939 is about 263.4929959840.

The spelling of 18293939 in words is "eighteen million, two hundred ninety-three thousand, nine hundred thirty-nine".