21213122131212 has 96 divisors (see below), whose sum is σ = 54491738321664. Its totient is φ = 6369361152000.

The previous prime is 21213122131181. The next prime is 21213122131219.

21213122131212 is nontrivially palindromic in base 10.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (21213122131219) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 48363087 + ... + 48799737.

It is an arithmetic number, because the mean of its divisors is an integer number (567622274184).

Almost surely, 2^{21213122131212} is an apocalyptic number.

21213122131212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21213122131212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27245869160832).

21213122131212 is an abundant number, since it is smaller than the sum of its proper divisors (33278616190452).

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

21213122131212 is a wasteful number, since it uses less digits than its factorization.

21213122131212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440039 (or 440037 counting only the distinct ones).

The product of its digits is 576, while the sum is 24.

It can be divided in two parts, 2121312 and 2131212, that added together give a palindrome (4252524).

The spelling of 21213122131212 in words is "twenty-one trillion, two hundred thirteen billion, one hundred twenty-two million, one hundred thirty-one thousand, two hundred twelve".