21122221322320 has 40 divisors (see below), whose sum is σ = 49191979464936. Its totient is φ = 8434640805888.

The previous prime is 21122221322263. The next prime is 21122221322327. The reversal of 21122221322320 is 2322312222112.

It can be written as a sum of positive squares in 4 ways, for example, as 6233550837264 + 14888670485056 = 2496708^2 + 3858584^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×21122221322320² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122221322327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 222572937 + ... + 222667816.

Almost surely, 2^{21122221322320} is an apocalyptic number.

21122221322320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21122221322320 is an abundant number, since it is smaller than the sum of its proper divisors (28069758142616).

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

21122221322320 is a wasteful number, since it uses less digits than its factorization.

21122221322320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445241359 (or 445241353 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 21122221322320 its reverse (2322312222112), we get a palindrome (23444533544432).

The spelling of 21122221322320 in words is "twenty-one trillion, one hundred twenty-two billion, two hundred twenty-one million, three hundred twenty-two thousand, three hundred twenty".