21404404241 has 16 divisors (see below), whose sum is σ = 23701906368. Its totient is φ = 19166227200.

The previous prime is 21404404223. The next prime is 21404404247. The reversal of 21404404241 is 14240440412.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21404404241 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21404404241.

It is not an unprimeable number, because it can be changed into a prime (21404404247) 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, 593570 + ... + 628596.

It is an arithmetic number, because the mean of its divisors is an integer number (1481369148).

Almost surely, 2^21404404241 is an apocalyptic number.

It is an amenable number.

21404404241 is a deficient number, since it is larger than the sum of its proper divisors (2297502127).

21404404241 is a wasteful number, since it uses less digits than its factorization.

21404404241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35872.

The product of its (nonzero) digits is 4096, while the sum is 26.

Adding to 21404404241 its reverse (14240440412), we get a palindrome (35644844653).

The spelling of 21404404241 in words is "twenty-one billion, four hundred four million, four hundred four thousand, two hundred forty-one".