21011021011220 has 48 divisors (see below), whose sum is σ = 44181779592720. Its totient is φ = 8393244447744.

The previous prime is 21011021011193. The next prime is 21011021011229. The reversal of 21011021011220 is 2211012011012.

It can be written as a sum of positive squares in 8 ways, for example, as 10242739383184 + 10768281628036 = 3200428^2 + 3281506^2 .

It is a super-2 number, since 2×21011021011220² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21011021011195 and 21011021011204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011021011229) 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 15 ways as a sum of consecutive naturals, for example, 72510386 + ... + 72799574.

It is an arithmetic number, because the mean of its divisors is an integer number (920453741515).

Almost surely, 2^{21011021011220} is an apocalyptic number.

21011021011220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011021011220 is an abundant number, since it is smaller than the sum of its proper divisors (23170758581500).

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

21011021011220 is a wasteful number, since it uses less digits than its factorization.

21011021011220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294012 (or 294010 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21011021011220 its reverse (2211012011012), we get a palindrome (23222033022232).

The spelling of 21011021011220 in words is "twenty-one trillion, eleven billion, twenty-one million, eleven thousand, two hundred twenty".