21321043431401 has 16 divisors (see below), whose sum is σ = 24419000893440. Its totient is φ = 18236151101520.

The previous prime is 21321043431293. The next prime is 21321043431433. The reversal of 21321043431401 is 10413434012312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21321043431401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21321043431901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4420580 + ... + 7885658.

It is an arithmetic number, because the mean of its divisors is an integer number (1526187555840).

Almost surely, 2^{21321043431401} is an apocalyptic number.

It is an amenable number.

21321043431401 is a deficient number, since it is larger than the sum of its proper divisors (3097957462039).

21321043431401 is an equidigital number, since it uses as much as digits as its factorization.

21321043431401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3466964.

The product of its (nonzero) digits is 6912, while the sum is 29.

Adding to 21321043431401 its reverse (10413434012312), we get a palindrome (31734477443713).

The spelling of 21321043431401 in words is "twenty-one trillion, three hundred twenty-one billion, forty-three million, four hundred thirty-one thousand, four hundred one".