21010021221220 has 48 divisors (see below), whose sum is σ = 45005851437120. Its totient is φ = 8235843048576.

The previous prime is 21010021221193. The next prime is 21010021221227. The reversal of 21010021221220 is 2212212001012.

It is a happy number.

It is a super-2 number, since 2×21010021221220² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21010021221194 and 21010021221203.

It is not an unprimeable number, because it can be changed into a prime (21010021221227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10626582 + ... + 12447661.

It is an arithmetic number, because the mean of its divisors is an integer number (937621904940).

Almost surely, 2^{21010021221220} is an apocalyptic number.

21010021221220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010021221220 is an abundant number, since it is smaller than the sum of its proper divisors (23995830215900).

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

21010021221220 is a wasteful number, since it uses less digits than its factorization.

21010021221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23075164 (or 23075162 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21010021221220 its reverse (2212212001012), we get a palindrome (23222233222232).

The spelling of 21010021221220 in words is "twenty-one trillion, ten billion, twenty-one million, two hundred twenty-one thousand, two hundred twenty".