21198196 has 6 divisors (see below), whose sum is σ = 37096850. Its totient is φ = 10599096.

The previous prime is 21198187. The next prime is 21198223. The reversal of 21198196 is 69189112.

It can be written as a sum of positive squares in only one way, i.e., 14333796 + 6864400 = 3786^2 + 2620^2 .

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 as a sum of consecutive naturals, namely, 2649771 + ... + 2649778.

Almost surely, 2^21198196 is an apocalyptic number.

It is an amenable number.

21198196 is a deficient number, since it is larger than the sum of its proper divisors (15898654).

21198196 is a wasteful number, since it uses less digits than its factorization.

21198196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5299553 (or 5299551 counting only the distinct ones).

The product of its digits is 7776, while the sum is 37.

The square root of 21198196 is about 4604.1498672393. The cubic root of 21198196 is about 276.7576501137.

The spelling of 21198196 in words is "twenty-one million, one hundred ninety-eight thousand, one hundred ninety-six".