18189742 has 4 divisors (see below), whose sum is σ = 27284616. Its totient is φ = 9094870.

The previous prime is 18189727. The next prime is 18189751. The reversal of 18189742 is 24798181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24798181 = 229 ⋅108289.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 18189695 and 18189704.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4547434 + ... + 4547437.

It is an arithmetic number, because the mean of its divisors is an integer number (6821154).

Almost surely, 2^18189742 is an apocalyptic number.

18189742 is a deficient number, since it is larger than the sum of its proper divisors (9094874).

18189742 is an equidigital number, since it uses as much as digits as its factorization.

18189742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9094873.

The product of its digits is 32256, while the sum is 40.

The square root of 18189742 is about 4264.9433759430. The cubic root of 18189742 is about 262.9917831530.

The spelling of 18189742 in words is "eighteen million, one hundred eighty-nine thousand, seven hundred forty-two".