13040221 has 4 divisors (see below), whose sum is σ = 13115772. Its totient is φ = 12964672.

The previous prime is 13040219. The next prime is 13040231. The reversal of 13040221 is 12204031.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12204031 = 7 ⋅1743433.

It can be written as a sum of positive squares in 2 ways, for example, as 11799225 + 1240996 = 3435^2 + 1114^2 .

It is a cyclic number.

It is not a de Polignac number, because 13040221 - 2¹ = 13040219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13040231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37516 + ... + 37861.

It is an arithmetic number, because the mean of its divisors is an integer number (3278943).

Almost surely, 2^13040221 is an apocalyptic number.

It is an amenable number.

13040221 is a deficient number, since it is larger than the sum of its proper divisors (75551).

13040221 is an equidigital number, since it uses as much as digits as its factorization.

13040221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75550.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 13040221 is about 3611.1246170688. The cubic root of 13040221 is about 235.3757140692.

Adding to 13040221 its reverse (12204031), we get a palindrome (25244252).

The spelling of 13040221 in words is "thirteen million, forty thousand, two hundred twenty-one".