20031423213421 has 2 divisors, whose sum is σ = 20031423213422. Its totient is φ = 20031423213420.

The previous prime is 20031423213409. The next prime is 20031423213437. The reversal of 20031423213421 is 12431232413002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19193914539396 + 837508674025 = 4381086^2 + 915155^2 .

It is a cyclic number.

It is not a de Polignac number, because 20031423213421 - 2¹⁵ = 20031423180653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20031423213421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20031423213821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10015711606710 + 10015711606711.

It is an arithmetic number, because the mean of its divisors is an integer number (10015711606711).

Almost surely, 2^{20031423213421} is an apocalyptic number.

It is an amenable number.

20031423213421 is a deficient number, since it is larger than the sum of its proper divisors (1).

20031423213421 is an equidigital number, since it uses as much as digits as its factorization.

20031423213421 is an evil number, because the sum of its binary digits is even.

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

Adding to 20031423213421 its reverse (12431232413002), we get a palindrome (32462655626423).

The spelling of 20031423213421 in words is "twenty trillion, thirty-one billion, four hundred twenty-three million, two hundred thirteen thousand, four hundred twenty-one".