21404421320011 has 4 divisors (see below), whose sum is σ = 21662305914312. Its totient is φ = 21146536725712.

The previous prime is 21404421319991. The next prime is 21404421320017. The reversal of 21404421320011 is 11002312440412.

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-21404421320011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21404421320017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128942297026 + ... + 128942297191.

It is an arithmetic number, because the mean of its divisors is an integer number (5415576478578).

Almost surely, 2^{21404421320011} is an apocalyptic number.

21404421320011 is a deficient number, since it is larger than the sum of its proper divisors (257884594301).

21404421320011 is an equidigital number, since it uses as much as digits as its factorization.

21404421320011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257884594300.

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

Adding to 21404421320011 its reverse (11002312440412), we get a palindrome (32406733760423).

The spelling of 21404421320011 in words is "twenty-one trillion, four hundred four billion, four hundred twenty-one million, three hundred twenty thousand, eleven".