21010212111220 has 48 divisors (see below), whose sum is σ = 44253959939280. Its totient is φ = 8378845784064.

The previous prime is 21010212111209. The next prime is 21010212111223. The reversal of 21010212111220 is 2211121201012.

It can be written as a sum of positive squares in 8 ways, for example, as 3377552947344 + 17632659163876 = 1837812^2 + 4199126^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21010212111194 and 21010212111203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010212111223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 347194326 + ... + 347254834.

It is an arithmetic number, because the mean of its divisors is an integer number (921957498735).

Almost surely, 2^{21010212111220} is an apocalyptic number.

21010212111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010212111220 is an abundant number, since it is smaller than the sum of its proper divisors (23243747828060).

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

21010212111220 is a wasteful number, since it uses less digits than its factorization.

21010212111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112372 (or 112370 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21010212111220 its reverse (2211121201012), we get a palindrome (23221333312232).

The spelling of 21010212111220 in words is "twenty-one trillion, ten billion, two hundred twelve million, one hundred eleven thousand, two hundred twenty".