20231321220 has 144 divisors (see below), whose sum is σ = 70470953280. Its totient is φ = 4646419200.

The previous prime is 20231321213. The next prime is 20231321293. The reversal of 20231321220 is 2212313202.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 20231321193 and 20231321202.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 231271 + ... + 306510.

It is an arithmetic number, because the mean of its divisors is an integer number (489381620).

Almost surely, 2^20231321220 is an apocalyptic number.

20231321220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20231321220 is an abundant number, since it is smaller than the sum of its proper divisors (50239632060).

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

20231321220 is a wasteful number, since it uses less digits than its factorization.

20231321220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537826 (or 537821 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 20231321220 its reverse (2212313202), we get a palindrome (22443634422).

The spelling of 20231321220 in words is "twenty billion, two hundred thirty-one million, three hundred twenty-one thousand, two hundred twenty".