20121220313 has 4 divisors (see below), whose sum is σ = 20770291968. Its totient is φ = 19472148660.

The previous prime is 20121220309. The next prime is 20121220319. The reversal of 20121220313 is 31302212102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20121220313 - 2² = 20121220309 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20121220291 and 20121220300.

It is not an unprimeable number, because it can be changed into a prime (20121220319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 324535781 + ... + 324535842.

It is an arithmetic number, because the mean of its divisors is an integer number (5192572992).

Almost surely, 2^20121220313 is an apocalyptic number.

It is an amenable number.

20121220313 is a deficient number, since it is larger than the sum of its proper divisors (649071655).

20121220313 is an equidigital number, since it uses as much as digits as its factorization.

20121220313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649071654.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 20121220313 its reverse (31302212102), we get a palindrome (51423432415).

The spelling of 20121220313 in words is "twenty billion, one hundred twenty-one million, two hundred twenty thousand, three hundred thirteen".