21443203423 has 8 divisors (see below), whose sum is σ = 21657332736. Its totient is φ = 21229188600.

The previous prime is 21443203417. The next prime is 21443203427. The reversal of 21443203423 is 32430234412.

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 21443203423 - 2⁵ = 21443203391 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21443203391 and 21443203400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21443203427) 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, 376218 + ... + 429448.

It is an arithmetic number, because the mean of its divisors is an integer number (2707166592).

Almost surely, 2^21443203423 is an apocalyptic number.

21443203423 is a deficient number, since it is larger than the sum of its proper divisors (214129313).

21443203423 is a wasteful number, since it uses less digits than its factorization.

21443203423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57245.

The product of its (nonzero) digits is 13824, while the sum is 28.

Adding to 21443203423 its reverse (32430234412), we get a palindrome (53873437835).

The spelling of 21443203423 in words is "twenty-one billion, four hundred forty-three million, two hundred three thousand, four hundred twenty-three".