13537621 has 2 divisors, whose sum is σ = 13537622. Its totient is φ = 13537620.

The previous prime is 13537619. The next prime is 13537649. The reversal of 13537621 is 12673531.

13537621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (13537649) can be obtained adding 13537621 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13032100 + 505521 = 3610^2 + 711^2 .

It is a cyclic number.

It is not a de Polignac number, because 13537621 - 2¹ = 13537619 is a prime.

Together with 13537619, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 13537621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13537651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6768810 + 6768811.

It is an arithmetic number, because the mean of its divisors is an integer number (6768811).

Almost surely, 2^13537621 is an apocalyptic number.

It is an amenable number.

13537621 is a deficient number, since it is larger than the sum of its proper divisors (1).

13537621 is an equidigital number, since it uses as much as digits as its factorization.

13537621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780, while the sum is 28.

The square root of 13537621 is about 3679.3506220528. The cubic root of 13537621 is about 238.3311364113.

The spelling of 13537621 in words is "thirteen million, five hundred thirty-seven thousand, six hundred twenty-one".