21120021320000 has 70 divisors (see below), whose sum is σ = 52370788965858. Its totient is φ = 8448008512000.

The previous prime is 21120021319997. The next prime is 21120021320023. The reversal of 21120021320000 is 2312002112.

It is a happy number.

It can be written as a sum of positive squares in 5 ways, for example, as 2535024414976 + 18584996905024 = 1592176^2 + 4311032^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 263960267 + ... + 264040266.

Almost surely, 2^{21120021320000} is an apocalyptic number.

21120021320000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120021320000 is an abundant number, since it is smaller than the sum of its proper divisors (31250767645858).

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

21120021320000 is an frugal number, since it uses more digits than its factorization.

21120021320000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 528000565 (or 528000540 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21120021320000 its reverse (2312002112), we get a palindrome (21122333322112).

The spelling of 21120021320000 in words is "twenty-one trillion, one hundred twenty billion, twenty-one million, three hundred twenty thousand".