21020220211212 has 144 divisors (see below), whose sum is σ = 56588081004000. Its totient is φ = 6556140656640.

The previous prime is 21020220211141. The next prime is 21020220211313. The reversal of 21020220211212 is 21211202202012.

It is a happy number.

21020220211212 is a `hidden beast` number, since 2 + 1 + 0 + 20 + 220 + 211 + 212 = 666.

It is a super-3 number, since 3×21020220211212³ (a number of 41 digits) contains 333 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 498312762 + ... + 498354942.

It is an arithmetic number, because the mean of its divisors is an integer number (392972784750).

Almost surely, 2^{21020220211212} 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 21020220211212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28294040502000).

21020220211212 is an abundant number, since it is smaller than the sum of its proper divisors (35567860792788).

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

21020220211212 is a wasteful number, since it uses less digits than its factorization.

21020220211212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46936 (or 46931 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21020220211212 its reverse (21211202202012), we get a palindrome (42231422413224).

The spelling of 21020220211212 in words is "twenty-one trillion, twenty billion, two hundred twenty million, two hundred eleven thousand, two hundred twelve".