21143100443 has 4 divisors (see below), whose sum is σ = 21144432768. Its totient is φ = 21141768120.

The previous prime is 21143100401. The next prime is 21143100463. The reversal of 21143100443 is 34400134112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21143100443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21143100463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 642068 + ... + 674193.

It is an arithmetic number, because the mean of its divisors is an integer number (5286108192).

Almost surely, 2^21143100443 is an apocalyptic number.

21143100443 is a deficient number, since it is larger than the sum of its proper divisors (1332325).

21143100443 is a wasteful number, since it uses less digits than its factorization.

21143100443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1332324.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21143100443 its reverse (34400134112), we get a palindrome (55543234555).

The spelling of 21143100443 in words is "twenty-one billion, one hundred forty-three million, one hundred thousand, four hundred forty-three".