21012301212 has 96 divisors (see below), whose sum is σ = 57024952320. Its totient is φ = 5897707200.

The previous prime is 21012301171. The next prime is 21012301213. The reversal of 21012301212 is 21210321012.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 21012301191 and 21012301200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012301213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2128087 + ... + 2137937.

It is an arithmetic number, because the mean of its divisors is an integer number (594009920).

Almost surely, 2^21012301212 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 21012301212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28512476160).

21012301212 is an abundant number, since it is smaller than the sum of its proper divisors (36012651108).

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

21012301212 is a wasteful number, since it uses less digits than its factorization.

21012301212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10311 (or 10309 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21012301212 its reverse (21210321012), we get a palindrome (42222622224).

The spelling of 21012301212 in words is "twenty-one billion, twelve million, three hundred one thousand, two hundred twelve".