20211221211 has 8 divisors (see below), whose sum is σ = 26956403280. Its totient is φ = 13470093312.

The previous prime is 20211221207. The next prime is 20211221221. The reversal of 20211221211 is 11212211202.

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

It is not a de Polignac number, because 20211221211 - 2² = 20211221207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20211221221) 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, 1001890 + ... + 1021863.

It is an arithmetic number, because the mean of its divisors is an integer number (3369550410).

Almost surely, 2^20211221211 is an apocalyptic number.

20211221211 is a deficient number, since it is larger than the sum of its proper divisors (6745182069).

20211221211 is a wasteful number, since it uses less digits than its factorization.

20211221211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2027085.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 20211221211 its reverse (11212211202), we get a palindrome (31423432413).

The spelling of 20211221211 in words is "twenty billion, two hundred eleven million, two hundred twenty-one thousand, two hundred eleven".