13401721637 has 2 divisors, whose sum is σ = 13401721638. Its totient is φ = 13401721636.

The previous prime is 13401721607. The next prime is 13401721643. The reversal of 13401721637 is 73612710431.

13401721637 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13290861796 + 110859841 = 115286^2 + 10529^2 .

It is a cyclic number.

It is not a de Polignac number, because 13401721637 - 2⁸ = 13401721381 is a prime.

It is a super-2 number, since 2×13401721637² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 13401721597 and 13401721606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13401721607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6700860818 + 6700860819.

It is an arithmetic number, because the mean of its divisors is an integer number (6700860819).

Almost surely, 2^13401721637 is an apocalyptic number.

It is an amenable number.

13401721637 is a deficient number, since it is larger than the sum of its proper divisors (1).

13401721637 is an equidigital number, since it uses as much as digits as its factorization.

13401721637 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21168, while the sum is 35.

The spelling of 13401721637 in words is "thirteen billion, four hundred one million, seven hundred twenty-one thousand, six hundred thirty-seven".