18688442 has 8 divisors (see below), whose sum is σ = 28091232. Its totient is φ = 9324700.

The previous prime is 18688433. The next prime is 18688447. The reversal of 18688442 is 24488681.

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

It is a self number, because there is not a number n which added to its sum of digits gives 18688442.

It is not an unprimeable number, because it can be changed into a prime (18688447) 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, 8534 + ... + 10497.

It is an arithmetic number, because the mean of its divisors is an integer number (3511404).

Almost surely, 2^18688442 is an apocalyptic number.

18688442 is a deficient number, since it is larger than the sum of its proper divisors (9402790).

18688442 is a wasteful number, since it uses less digits than its factorization.

18688442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19524.

The product of its digits is 98304, while the sum is 41.

The square root of 18688442 is about 4323.0130696078. The cubic root of 18688442 is about 265.3735896065.

The spelling of 18688442 in words is "eighteen million, six hundred eighty-eight thousand, four hundred forty-two".