21400423441 has 16 divisors (see below), whose sum is σ = 21856843008. Its totient is φ = 20949245200.

The previous prime is 21400423423. The next prime is 21400423453. The reversal of 21400423441 is 14432400412.

It is a cyclic number.

It is not a de Polignac number, because 21400423441 - 2¹⁷ = 21400292369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21400423841) 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, 10556670 + ... + 10558696.

It is an arithmetic number, because the mean of its divisors is an integer number (1366052688).

Almost surely, 2^21400423441 is an apocalyptic number.

It is an amenable number.

21400423441 is a deficient number, since it is larger than the sum of its proper divisors (456419567).

21400423441 is a wasteful number, since it uses less digits than its factorization.

21400423441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3212.

The product of its (nonzero) digits is 3072, while the sum is 25.

Adding to 21400423441 its reverse (14432400412), we get a palindrome (35832823853).

The spelling of 21400423441 in words is "twenty-one billion, four hundred million, four hundred twenty-three thousand, four hundred forty-one".