21421221343 has 8 divisors (see below), whose sum is σ = 21916586336. Its totient is φ = 20930508000.

The previous prime is 21421221337. The next prime is 21421221389. The reversal of 21421221343 is 34312212412.

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-21421221343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21421222343) 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, 1153596 + ... + 1172017.

It is an arithmetic number, because the mean of its divisors is an integer number (2739573292).

Almost surely, 2^21421221343 is an apocalyptic number.

21421221343 is a deficient number, since it is larger than the sum of its proper divisors (495364993).

21421221343 is a wasteful number, since it uses less digits than its factorization.

21421221343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2325825.

The product of its digits is 2304, while the sum is 25.

Adding to 21421221343 its reverse (34312212412), we get a palindrome (55733433755).

The spelling of 21421221343 in words is "twenty-one billion, four hundred twenty-one million, two hundred twenty-one thousand, three hundred forty-three".