20198638 has 8 divisors (see below), whose sum is σ = 30318120. Its totient is φ = 10092600.

The previous prime is 20198627. The next prime is 20198657. The reversal of 20198638 is 83689102.

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 = 20198597 and 20198606.

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 in 3 ways as a sum of consecutive naturals, for example, 2313 + ... + 6763.

It is an arithmetic number, because the mean of its divisors is an integer number (3789765).

Almost surely, 2^20198638 is an apocalyptic number.

20198638 is a deficient number, since it is larger than the sum of its proper divisors (10119482).

20198638 is a wasteful number, since it uses less digits than its factorization.

20198638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6722.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 20198638 is about 4494.2894877834. The cubic root of 20198638 is about 272.3374470302.

The spelling of 20198638 in words is "twenty million, one hundred ninety-eight thousand, six hundred thirty-eight".