21198364566 has 8 divisors (see below), whose sum is σ = 42396729144. Its totient is φ = 7066121520.

The previous prime is 21198364513. The next prime is 21198364597. The reversal of 21198364566 is 66546389112.

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

21198364566 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1766530375 + ... + 1766530386.

It is an arithmetic number, because the mean of its divisors is an integer number (5299591143).

Almost surely, 2^21198364566 is an apocalyptic number.

21198364566 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21198364566 is a wasteful number, since it uses less digits than its factorization.

21198364566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3533060766.

The product of its digits is 1866240, while the sum is 51.

The spelling of 21198364566 in words is "twenty-one billion, one hundred ninety-eight million, three hundred sixty-four thousand, five hundred sixty-six".