21240211204212 has 384 divisors, whose sum is σ = 68906190409728. Its totient is φ = 4954908879360.

The previous prime is 21240211204183. The next prime is 21240211204229.

21240211204212 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21240211204212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 53580243 + ... + 53975205.

It is an arithmetic number, because the mean of its divisors is an integer number (179443204192).

Almost surely, 2^{21240211204212} is an apocalyptic number.

21240211204212 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 21240211204212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34453095204864).

21240211204212 is an abundant number, since it is smaller than the sum of its proper divisors (47665979205516).

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

21240211204212 is a wasteful number, since it uses less digits than its factorization.

21240211204212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395060 (or 395036 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 24.

It can be divided in two parts, 2124021 and 1204212, that added together give a palindrome (3328233).

The spelling of 21240211204212 in words is "twenty-one trillion, two hundred forty billion, two hundred eleven million, two hundred four thousand, two hundred twelve".