21243424143 has 16 divisors (see below), whose sum is σ = 29323514880. Its totient is φ = 13663549536.

The previous prime is 21243424123. The next prime is 21243424187. The reversal of 21243424143 is 34142434212.

It is not a de Polignac number, because 21243424143 - 2¹² = 21243420047 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21243424143.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243424123) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23446 + ... + 207452.

It is an arithmetic number, because the mean of its divisors is an integer number (1832719680).

Almost surely, 2^21243424143 is an apocalyptic number.

21243424143 is a deficient number, since it is larger than the sum of its proper divisors (8080090737).

21243424143 is a wasteful number, since it uses less digits than its factorization.

21243424143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185366.

The product of its digits is 18432, while the sum is 30.

Adding to 21243424143 its reverse (34142434212), we get a palindrome (55385858355).

The spelling of 21243424143 in words is "twenty-one billion, two hundred forty-three million, four hundred twenty-four thousand, one hundred forty-three".