21022221986 has 8 divisors (see below), whose sum is σ = 31858419180. Its totient is φ = 10402748928.

The previous prime is 21022221923. The next prime is 21022222007. The reversal of 21022221986 is 68912222012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20236485025 + 785736961 = 142255^2 + 28031^2 .

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

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, 54180791 + ... + 54181178.

Almost surely, 2^21022221986 is an apocalyptic number.

21022221986 is a deficient number, since it is larger than the sum of its proper divisors (10836197194).

21022221986 is a wasteful number, since it uses less digits than its factorization.

21022221986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108362068.

The product of its (nonzero) digits is 13824, while the sum is 35.

Adding to 21022221986 its reverse (68912222012), we get a palindrome (89934443998).

The spelling of 21022221986 in words is "twenty-one billion, twenty-two million, two hundred twenty-one thousand, nine hundred eighty-six".