18122939 has 4 divisors (see below), whose sum is σ = 18132456. Its totient is φ = 18113424.

The previous prime is 18122927. The next prime is 18122947. The reversal of 18122939 is 93922181.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18122939 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 18122899 and 18122908.

It is not an unprimeable number, because it can be changed into a prime (18122989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 809 + ... + 6074.

It is an arithmetic number, because the mean of its divisors is an integer number (4533114).

Almost surely, 2^18122939 is an apocalyptic number.

18122939 is a deficient number, since it is larger than the sum of its proper divisors (9517).

18122939 is an equidigital number, since it uses as much as digits as its factorization.

18122939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9516.

The product of its digits is 7776, while the sum is 35.

The square root of 18122939 is about 4257.1045324258. The cubic root of 18122939 is about 262.6694367924.

The spelling of 18122939 in words is "eighteen million, one hundred twenty-two thousand, nine hundred thirty-nine".