21144203243 has 8 divisors (see below), whose sum is σ = 21556983168. Its totient is φ = 20731935744.

The previous prime is 21144203239. The next prime is 21144203287. The reversal of 21144203243 is 34230244112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21144203243 - 2² = 21144203239 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21144208243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44246 + ... + 210347.

It is an arithmetic number, because the mean of its divisors is an integer number (2694622896).

Almost surely, 2^21144203243 is an apocalyptic number.

21144203243 is a deficient number, since it is larger than the sum of its proper divisors (412779925).

21144203243 is a wasteful number, since it uses less digits than its factorization.

21144203243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256213.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21144203243 its reverse (34230244112), we get a palindrome (55374447355).

The spelling of 21144203243 in words is "twenty-one billion, one hundred forty-four million, two hundred three thousand, two hundred forty-three".