21021212122311 has 4 divisors (see below), whose sum is σ = 28028282829752. Its totient is φ = 14014141414872.

The previous prime is 21021212122291. The next prime is 21021212122321. The reversal of 21021212122311 is 11322121212012.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21021212122311 - 2⁶ = 21021212122247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021212122321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3503535353716 + ... + 3503535353721.

It is an arithmetic number, because the mean of its divisors is an integer number (7007070707438).

Almost surely, 2^{21021212122311} is an apocalyptic number.

21021212122311 is a deficient number, since it is larger than the sum of its proper divisors (7007070707441).

21021212122311 is an equidigital number, since it uses as much as digits as its factorization.

21021212122311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7007070707440.

The product of its (nonzero) digits is 192, while the sum is 21.

Adding to 21021212122311 its reverse (11322121212012), we get a palindrome (32343333334323).

The spelling of 21021212122311 in words is "twenty-one trillion, twenty-one billion, two hundred twelve million, one hundred twenty-two thousand, three hundred eleven".