21221412043 has 4 divisors (see below), whose sum is σ = 22853828368. Its totient is φ = 19588995720.

The previous prime is 21221412019. The next prime is 21221412071. The reversal of 21221412043 is 34021412212.

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

It is a cyclic number.

It is not a de Polignac number, because 21221412043 - 2²¹ = 21219314891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221412083) 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, 816208143 + ... + 816208168.

It is an arithmetic number, because the mean of its divisors is an integer number (5713457092).

Almost surely, 2^21221412043 is an apocalyptic number.

21221412043 is a deficient number, since it is larger than the sum of its proper divisors (1632416325).

21221412043 is a wasteful number, since it uses less digits than its factorization.

21221412043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1632416324.

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21221412043 its reverse (34021412212), we get a palindrome (55242824255).

The spelling of 21221412043 in words is "twenty-one billion, two hundred twenty-one million, four hundred twelve thousand, forty-three".