20221221320 has 64 divisors (see below), whose sum is σ = 46639378800. Its totient is φ = 7885803520.

The previous prime is 20221221301. The next prime is 20221221329. The reversal of 20221221320 is 2312212202.

It can be written as a sum of positive squares in 8 ways, for example, as 8945754724 + 11275466596 = 94582^2 + 106186^2 .

It is not an unprimeable number, because it can be changed into a prime (20221221329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3074996 + ... + 3081564.

Almost surely, 2^20221221320 is an apocalyptic number.

20221221320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20221221320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23319689400).

20221221320 is an abundant number, since it is smaller than the sum of its proper divisors (26418157480).

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

20221221320 is a wasteful number, since it uses less digits than its factorization.

20221221320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8498 (or 8494 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 20221221320 its reverse (2312212202), we get a palindrome (22533433522).

The spelling of 20221221320 in words is "twenty billion, two hundred twenty-one million, two hundred twenty-one thousand, three hundred twenty".