21421121443 has 8 divisors (see below), whose sum is σ = 21496946688. Its totient is φ = 21345400584.

The previous prime is 21421121437. The next prime is 21421121497. The reversal of 21421121443 is 34412112412.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21421121443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21421121143) 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, 397096 + ... + 447802.

It is an arithmetic number, because the mean of its divisors is an integer number (2687118336).

Almost surely, 2^21421121443 is an apocalyptic number.

21421121443 is a deficient number, since it is larger than the sum of its proper divisors (75825245).

21421121443 is a wasteful number, since it uses less digits than its factorization.

21421121443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52193.

The product of its digits is 1536, while the sum is 25.

Adding to 21421121443 its reverse (34412112412), we get a palindrome (55833233855).

The spelling of 21421121443 in words is "twenty-one billion, four hundred twenty-one million, one hundred twenty-one thousand, four hundred forty-three".