18207842 has 4 divisors (see below), whose sum is σ = 27311766. Its totient is φ = 9103920.

The previous prime is 18207809. The next prime is 18207857. The reversal of 18207842 is 24870281.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 12538681 + 5669161 = 3541^2 + 2381^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18207799 and 18207808.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 4551959 + ... + 4551962.

Almost surely, 2^18207842 is an apocalyptic number.

18207842 is a deficient number, since it is larger than the sum of its proper divisors (9103924).

18207842 is an equidigital number, since it uses as much as digits as its factorization.

18207842 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9103923.

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 18207842 is about 4267.0647991330. The cubic root of 18207842 is about 263.0789856590.

The spelling of 18207842 in words is "eighteen million, two hundred seven thousand, eight hundred forty-two".