21221201086 has 16 divisors (see below), whose sum is σ = 32092485120. Its totient is φ = 10523843200.

The previous prime is 21221201059. The next prime is 21221201087. The reversal of 21221201086 is 68010212212.

It is a self number, because there is not a number n which added to its sum of digits gives 21221201086.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221201087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 281730 + ... + 349018.

It is an arithmetic number, because the mean of its divisors is an integer number (2005780320).

Almost surely, 2^21221201086 is an apocalyptic number.

21221201086 is a deficient number, since it is larger than the sum of its proper divisors (10871284034).

21221201086 is a wasteful number, since it uses less digits than its factorization.

21221201086 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68579.

The product of its (nonzero) digits is 768, while the sum is 25.

Adding to 21221201086 its reverse (68010212212), we get a palindrome (89231413298).

The spelling of 21221201086 in words is "twenty-one billion, two hundred twenty-one million, two hundred one thousand, eighty-six".