21212212011121 has 8 divisors (see below), whose sum is σ = 21527115706880. Its totient is φ = 20898468182592.

The previous prime is 21212212011061. The next prime is 21212212011187. The reversal of 21212212011121 is 12111021221212.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21212212011121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212212411121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 289929960 + ... + 290003113.

It is an arithmetic number, because the mean of its divisors is an integer number (2690889463360).

Almost surely, 2^{21212212011121} is an apocalyptic number.

It is an amenable number.

21212212011121 is a deficient number, since it is larger than the sum of its proper divisors (314903695759).

21212212011121 is an equidigital number, since it uses as much as digits as its factorization.

21212212011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 579933615.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21212212011121 its reverse (12111021221212), we get a palindrome (33323233232333).

The spelling of 21212212011121 in words is "twenty-one trillion, two hundred twelve billion, two hundred twelve million, eleven thousand, one hundred twenty-one".