13211020421 has 4 divisors (see below), whose sum is σ = 13215259200. Its totient is φ = 13206781644.

The previous prime is 13211020387. The next prime is 13211020423. The reversal of 13211020421 is 12402011231.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12402011231 = 397 ⋅31239323.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13211020421 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 13211020421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13211020423) 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, 2114711 + ... + 2120948.

It is an arithmetic number, because the mean of its divisors is an integer number (3303814800).

Almost surely, 2^13211020421 is an apocalyptic number.

It is an amenable number.

13211020421 is a deficient number, since it is larger than the sum of its proper divisors (4238779).

13211020421 is an equidigital number, since it uses as much as digits as its factorization.

13211020421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4238778.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 13211020421 its reverse (12402011231), we get a palindrome (25613031652).

The spelling of 13211020421 in words is "thirteen billion, two hundred eleven million, twenty thousand, four hundred twenty-one".