13145443021 has 12 divisors (see below), whose sum is σ = 13421282332. Its totient is φ = 12875042304.

The previous prime is 13145443013. The next prime is 13145443039. The reversal of 13145443021 is 12034454131.

It can be written as a sum of positive squares in 2 ways, for example, as 5623350121 + 7522092900 = 74989^2 + 86730^2 .

It is not a de Polignac number, because 13145443021 - 2³ = 13145443013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13145443061) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 957421 + ... + 971053.

Almost surely, 2^13145443021 is an apocalyptic number.

It is an amenable number.

13145443021 is a deficient number, since it is larger than the sum of its proper divisors (275839311).

13145443021 is an equidigital number, since it uses as much as digits as its factorization.

13145443021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14028 (or 13969 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

Adding to 13145443021 its reverse (12034454131), we get a palindrome (25179897152).

The spelling of 13145443021 in words is "thirteen billion, one hundred forty-five million, four hundred forty-three thousand, twenty-one".