13404400021 has 2 divisors, whose sum is σ = 13404400022. Its totient is φ = 13404400020.

The previous prime is 13404399979. The next prime is 13404400033. The reversal of 13404400021 is 12000440431.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10244273796 + 3160126225 = 101214^2 + 56215^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13404400021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13404404021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6702200010 + 6702200011.

It is an arithmetic number, because the mean of its divisors is an integer number (6702200011).

Almost surely, 2^13404400021 is an apocalyptic number.

It is an amenable number.

13404400021 is a deficient number, since it is larger than the sum of its proper divisors (1).

13404400021 is an equidigital number, since it uses as much as digits as its factorization.

13404400021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 13404400021 its reverse (12000440431), we get a palindrome (25404840452).

The spelling of 13404400021 in words is "thirteen billion, four hundred four million, four hundred thousand, twenty-one".