21213121111211 has 8 divisors (see below), whose sum is σ = 21218701608720. Its totient is φ = 21207541362592.

The previous prime is 21213121111151. The next prime is 21213121111219. The reversal of 21213121111211 is 11211112131212.

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

It is a cyclic number.

It is not a de Polignac number, because 21213121111211 - 2²² = 21213116916907 is a prime.

It is a super-2 number, since 2×21213121111211² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213121111219) 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, 58898585 + ... + 59257653.

It is an arithmetic number, because the mean of its divisors is an integer number (2652337701090).

Almost surely, 2^{21213121111211} is an apocalyptic number.

21213121111211 is a deficient number, since it is larger than the sum of its proper divisors (5580497509).

21213121111211 is an equidigital number, since it uses as much as digits as its factorization.

21213121111211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 374445.

The product of its digits is 48, while the sum is 20.

Adding to 21213121111211 its reverse (11211112131212), we get a palindrome (32424233242423).

The spelling of 21213121111211 in words is "twenty-one trillion, two hundred thirteen billion, one hundred twenty-one million, one hundred eleven thousand, two hundred eleven".