21320301212 has 72 divisors (see below), whose sum is σ = 45054696960. Its totient is φ = 8792673120.

The previous prime is 21320301199. The next prime is 21320301253. The reversal of 21320301212 is 21210302312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1077803 + ... + 1097405.

It is an arithmetic number, because the mean of its divisors is an integer number (625759680).

Almost surely, 2^21320301212 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 21320301212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22527348480).

21320301212 is an abundant number, since it is smaller than the sum of its proper divisors (23734395748).

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

21320301212 is a wasteful number, since it uses less digits than its factorization.

21320301212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19831 (or 19822 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21320301212 its reverse (21210302312), we get a palindrome (42530603524).

The spelling of 21320301212 in words is "twenty-one billion, three hundred twenty million, three hundred one thousand, two hundred twelve".