21020231110212 has 168 divisors, whose sum is σ = 55631871935640. Its totient is φ = 6946154611200.

The previous prime is 21020231110189. The next prime is 21020231110213. The reversal of 21020231110212 is 21201113202012.

21020231110212 is a `hidden beast` number, since 210 + 2 + 0 + 231 + 1 + 10 + 212 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 513951345216 + 20506279764996 = 716904^2 + 4528386^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (21020231110213) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 155521462 + ... + 155656562.

It is an arithmetic number, because the mean of its divisors is an integer number (331142094855).

Almost surely, 2^{21020231110212} 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 21020231110212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27815935967820).

21020231110212 is an abundant number, since it is smaller than the sum of its proper divisors (34611640825428).

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

21020231110212 is a wasteful number, since it uses less digits than its factorization.

21020231110212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135585 (or 135568 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21020231110212 its reverse (21201113202012), we get a palindrome (42221344312224).

The spelling of 21020231110212 in words is "twenty-one trillion, twenty billion, two hundred thirty-one million, one hundred ten thousand, two hundred twelve".