13281621 has 8 divisors (see below), whose sum is σ = 17808480. Its totient is φ = 8804592.

The previous prime is 13281617. The next prime is 13281629. The reversal of 13281621 is 12618231.

13281621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 13281621 - 2² = 13281617 is a prime.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 13281591 and 13281600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13281629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11830 + ... + 12903.

It is an arithmetic number, because the mean of its divisors is an integer number (2226060).

Almost surely, 2^13281621 is an apocalyptic number.

It is an amenable number.

13281621 is a deficient number, since it is larger than the sum of its proper divisors (4526859).

13281621 is a wasteful number, since it uses less digits than its factorization.

13281621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24915.

The product of its digits is 576, while the sum is 24.

The square root of 13281621 is about 3644.3958347029. The cubic root of 13281621 is about 236.8192643678.

Adding to 13281621 its reverse (12618231), we get a palindrome (25899852).

The spelling of 13281621 in words is "thirteen million, two hundred eighty-one thousand, six hundred twenty-one".