18719998 has 16 divisors (see below), whose sum is σ = 31023360. Its totient is φ = 8400600.

The previous prime is 18719983. The next prime is 18720083. The reversal of 18719998 is 89991781.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3648 + ... + 7123.

It is an arithmetic number, because the mean of its divisors is an integer number (1938960).

Almost surely, 2^18719998 is an apocalyptic number.

18719998 is a deficient number, since it is larger than the sum of its proper divisors (12303362).

18719998 is a wasteful number, since it uses less digits than its factorization.

18719998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10863.

The product of its digits is 326592, while the sum is 52.

The square root of 18719998 is about 4326.6612994317. The cubic root of 18719998 is about 265.5228693964.

The spelling of 18719998 in words is "eighteen million, seven hundred nineteen thousand, nine hundred ninety-eight".