18939242 has 8 divisors (see below), whose sum is σ = 32467296. Its totient is φ = 8116812.

The previous prime is 18939211. The next prime is 18939247. The reversal of 18939242 is 24293981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 18939196 and 18939205.

It is not an unprimeable number, because it can be changed into a prime (18939247) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 676388 + ... + 676415.

It is an arithmetic number, because the mean of its divisors is an integer number (4058412).

Almost surely, 2^18939242 is an apocalyptic number.

18939242 is a deficient number, since it is larger than the sum of its proper divisors (13528054).

18939242 is a wasteful number, since it uses less digits than its factorization.

18939242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352812.

The product of its digits is 31104, while the sum is 38.

The square root of 18939242 is about 4351.9239423501. The cubic root of 18939242 is about 266.5554282568. Note that the first 3 decimals are identical.

The spelling of 18939242 in words is "eighteen million, nine hundred thirty-nine thousand, two hundred forty-two".