18005939 has 16 divisors (see below), whose sum is σ = 22252800. Its totient is φ = 14222304.

The previous prime is 18005927. The next prime is 18005959. The reversal of 18005939 is 93950081.

It is a cyclic number.

It is not a de Polignac number, because 18005939 - 2¹² = 18001843 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 18005899 and 18005908.

It is not an unprimeable number, because it can be changed into a prime (18005909) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3092 + ... + 6750.

It is an arithmetic number, because the mean of its divisors is an integer number (1390800).

Almost surely, 2^18005939 is an apocalyptic number.

18005939 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

18005939 is a deficient number, since it is larger than the sum of its proper divisors (4246861).

18005939 is a wasteful number, since it uses less digits than its factorization.

18005939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3722.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 18005939 is about 4243.3405472575. The cubic root of 18005939 is about 262.1029595536.

The spelling of 18005939 in words is "eighteen million, five thousand, nine hundred thirty-nine".