21343215133421 has 16 divisors (see below), whose sum is σ = 21905870807808. Its totient is φ = 20788809148800.

The previous prime is 21343215133381. The next prime is 21343215133433. The reversal of 21343215133421 is 12433151234312.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21343215133421 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 (21343215133321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 387416 + ... + 6544961.

It is an arithmetic number, because the mean of its divisors is an integer number (1369116925488).

Almost surely, 2^{21343215133421} is an apocalyptic number.

It is an amenable number.

21343215133421 is a deficient number, since it is larger than the sum of its proper divisors (562655674387).

21343215133421 is a wasteful number, since it uses less digits than its factorization.

21343215133421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6932972.

The product of its digits is 51840, while the sum is 35.

Adding to 21343215133421 its reverse (12433151234312), we get a palindrome (33776366367733).

The spelling of 21343215133421 in words is "twenty-one trillion, three hundred forty-three billion, two hundred fifteen million, one hundred thirty-three thousand, four hundred twenty-one".