20313043221421 has 4 divisors (see below), whose sum is σ = 20348247802972. Its totient is φ = 20277838639872.

The previous prime is 20313043221397. The next prime is 20313043221437. The reversal of 20313043221421 is 12412234031302.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14234283937225 + 6078759284196 = 3772835^2 + 2465514^2 .

It is a cyclic number.

It is not a de Polignac number, because 20313043221421 - 2⁵ = 20313043221389 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20313043221421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20313043222421) 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, 17602289910 + ... + 17602291063.

It is an arithmetic number, because the mean of its divisors is an integer number (5087061950743).

Almost surely, 2^{20313043221421} is an apocalyptic number.

It is an amenable number.

20313043221421 is a deficient number, since it is larger than the sum of its proper divisors (35204581551).

20313043221421 is an equidigital number, since it uses as much as digits as its factorization.

20313043221421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35204581550.

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 20313043221421 its reverse (12412234031302), we get a palindrome (32725277252723).

The spelling of 20313043221421 in words is "twenty trillion, three hundred thirteen billion, forty-three million, two hundred twenty-one thousand, four hundred twenty-one".