20001213220 has 48 divisors (see below), whose sum is σ = 42170713200. Its totient is φ = 7968522240.

The previous prime is 20001213217. The next prime is 20001213223. The reversal of 20001213220 is 2231210002.

It is an interprime number because it is at equal distance from previous prime (20001213217) and next prime (20001213223).

It can be written as a sum of positive squares in 8 ways, for example, as 1091113024 + 18910100196 = 33032^2 + 137514^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20001213220.

It is not an unprimeable number, because it can be changed into a prime (20001213223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6473436 + ... + 6476524.

It is an arithmetic number, because the mean of its divisors is an integer number (878556525).

Almost surely, 2^20001213220 is an apocalyptic number.

20001213220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20001213220 is an abundant number, since it is smaller than the sum of its proper divisors (22169499980).

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

20001213220 is a wasteful number, since it uses less digits than its factorization.

20001213220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4288 (or 4286 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 20001213220 its reverse (2231210002), we get a palindrome (22232423222).

The spelling of 20001213220 in words is "twenty billion, one million, two hundred thirteen thousand, two hundred twenty".