13405121 has 4 divisors (see below), whose sum is σ = 13716912. Its totient is φ = 13093332.

The previous prime is 13405111. The next prime is 13405123. The reversal of 13405121 is 12150431.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 13405121 - 2⁶ = 13405057 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13405121.

It is not an unprimeable number, because it can be changed into a prime (13405123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155831 + ... + 155916.

It is an arithmetic number, because the mean of its divisors is an integer number (3429228).

Almost surely, 2^13405121 is an apocalyptic number.

It is an amenable number.

13405121 is a deficient number, since it is larger than the sum of its proper divisors (311791).

13405121 is an equidigital number, since it uses as much as digits as its factorization.

13405121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311790.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 13405121 is about 3661.3004520252. The cubic root of 13405121 is about 237.5510272631.

Adding to 13405121 its reverse (12150431), we get a palindrome (25555552).

The spelling of 13405121 in words is "thirteen million, four hundred five thousand, one hundred twenty-one".