21323101221212 has 192 divisors, whose sum is σ = 47485791682560. Its totient is φ = 8162826845184.

The previous prime is 21323101221197. The next prime is 21323101221217. The reversal of 21323101221212 is 21212210132312.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323101221217) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3413331473 + ... + 3413337719.

It is an arithmetic number, because the mean of its divisors is an integer number (247321831680).

Almost surely, 2^{21323101221212} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21323101221212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23742895841280).

21323101221212 is an abundant number, since it is smaller than the sum of its proper divisors (26162690461348).

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

21323101221212 is a wasteful number, since it uses less digits than its factorization.

21323101221212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8680 (or 8678 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

Adding to 21323101221212 its reverse (21212210132312), we get a palindrome (42535311353524).

The spelling of 21323101221212 in words is "twenty-one trillion, three hundred twenty-three billion, one hundred one million, two hundred twenty-one thousand, two hundred twelve".