21021212212122 has 8 divisors (see below), whose sum is σ = 42042424424256. Its totient is φ = 7007070737372.

The previous prime is 21021212212111. The next prime is 21021212212123. The reversal of 21021212212122 is 22121221212012.

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

21021212212122 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21021212212123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1751767684338 + ... + 1751767684349.

It is an arithmetic number, because the mean of its divisors is an integer number (5255303053032).

Almost surely, 2^{21021212212122} is an apocalyptic number.

21021212212122 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21021212212122 is a wasteful number, since it uses less digits than its factorization.

21021212212122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3503535368692.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 21021212212122 its reverse (22121221212012), we get a palindrome (43142433424134).

The spelling of 21021212212122 in words is "twenty-one trillion, twenty-one billion, two hundred twelve million, two hundred twelve thousand, one hundred twenty-two".