21120220110020 has 12 divisors (see below), whose sum is σ = 44352462231084. Its totient is φ = 8448088044000.

The previous prime is 21120220110019. The next prime is 21120220110023. The reversal of 21120220110020 is 2001102202112.

It can be written as a sum of positive squares in 2 ways, for example, as 2470121442244 + 18650098667776 = 1571662^2 + 4318576^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21120220109977 and 21120220110004.

It is not an unprimeable number, because it can be changed into a prime (21120220110023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 528005502731 + ... + 528005502770.

It is an arithmetic number, because the mean of its divisors is an integer number (3696038519257).

Almost surely, 2^{21120220110020} is an apocalyptic number.

21120220110020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120220110020 is an abundant number, since it is smaller than the sum of its proper divisors (23232242121064).

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

21120220110020 is a wasteful number, since it uses less digits than its factorization.

21120220110020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056011005510 (or 1056011005508 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21120220110020 its reverse (2001102202112), we get a palindrome (23121322312132).

The spelling of 21120220110020 in words is "twenty-one trillion, one hundred twenty billion, two hundred twenty million, one hundred ten thousand, twenty".