21220122303440 has 20 divisors (see below), whose sum is σ = 49336784355684. Its totient is φ = 8488048921344.

The previous prime is 21220122303389. The next prime is 21220122303449. The reversal of 21220122303440 is 4430322102212.

It can be written as a sum of positive squares in 2 ways, for example, as 15904718277184 + 5315404026256 = 3988072^2 + 2305516^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21220122303449) 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, 132625764317 + ... + 132625764476.

Almost surely, 2^{21220122303440} is an apocalyptic number.

21220122303440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220122303440 is an abundant number, since it is smaller than the sum of its proper divisors (28116662052244).

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

21220122303440 is a wasteful number, since it uses less digits than its factorization.

21220122303440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265251528806 (or 265251528800 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21220122303440 its reverse (4430322102212), we get a palindrome (25650444405652).

The spelling of 21220122303440 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty-two million, three hundred three thousand, four hundred forty".