19998742 has 8 divisors (see below), whose sum is σ = 30197232. Its totient is φ = 9933000.

The previous prime is 19998733. The next prime is 19998743. The reversal of 19998742 is 24789991.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19998743) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32809 + ... + 33412.

It is an arithmetic number, because the mean of its divisors is an integer number (3774654).

Almost surely, 2^19998742 is an apocalyptic number.

19998742 is a deficient number, since it is larger than the sum of its proper divisors (10198490).

19998742 is a wasteful number, since it uses less digits than its factorization.

19998742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66374.

The product of its digits is 326592, while the sum is 49.

The square root of 19998742 is about 4471.9953041120. The cubic root of 19998742 is about 271.4360703112.

The spelling of 19998742 in words is "nineteen million, nine hundred ninety-eight thousand, seven hundred forty-two".