21443130243 has 20 divisors (see below), whose sum is σ = 32037867928. Its totient is φ = 14292948960.

The previous prime is 21443130223. The next prime is 21443130259. The reversal of 21443130243 is 34203134412.

It is not a de Polignac number, because 21443130243 - 2²¹ = 21441033091 is a prime.

It is a super-2 number, since 2×21443130243² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21443130223) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 530748 + ... + 569718.

Almost surely, 2^21443130243 is an apocalyptic number.

21443130243 is a deficient number, since it is larger than the sum of its proper divisors (10594737685).

21443130243 is an equidigital number, since it uses as much as digits as its factorization.

21443130243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45776 (or 45767 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 21443130243 its reverse (34203134412), we get a palindrome (55646264655).

The spelling of 21443130243 in words is "twenty-one billion, four hundred forty-three million, one hundred thirty thousand, two hundred forty-three".