13209121 has 2 divisors, whose sum is σ = 13209122. Its totient is φ = 13209120.

The previous prime is 13209109. The next prime is 13209139. The reversal of 13209121 is 12190231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9363600 + 3845521 = 3060^2 + 1961^2 .

It is an emirp because it is prime and its reverse (12190231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13209121 - 2⁵ = 13209089 is a prime.

It is not a weakly prime, because it can be changed into another prime (13209101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6604560 + 6604561.

It is an arithmetic number, because the mean of its divisors is an integer number (6604561).

Almost surely, 2^13209121 is an apocalyptic number.

It is an amenable number.

13209121 is a deficient number, since it is larger than the sum of its proper divisors (1).

13209121 is an equidigital number, since it uses as much as digits as its factorization.

13209121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 13209121 is about 3634.4354444673. The cubic root of 13209121 is about 236.3875717692.

Adding to 13209121 its reverse (12190231), we get a palindrome (25399352).

The spelling of 13209121 in words is "thirteen million, two hundred nine thousand, one hundred twenty-one".