13220643 has 4 divisors (see below), whose sum is σ = 17627528. Its totient is φ = 8813760.

The previous prime is 13220639. The next prime is 13220659. The reversal of 13220643 is 34602231.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 13220643 - 2² = 13220639 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13220633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2203438 + ... + 2203443.

It is an arithmetic number, because the mean of its divisors is an integer number (4406882).

Almost surely, 2^13220643 is an apocalyptic number.

13220643 is a deficient number, since it is larger than the sum of its proper divisors (4406885).

13220643 is an equidigital number, since it uses as much as digits as its factorization.

13220643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4406884.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 13220643 is about 3636.0202144653. The cubic root of 13220643 is about 236.4562835343.

Adding to 13220643 its reverse (34602231), we get a palindrome (47822874).

The spelling of 13220643 in words is "thirteen million, two hundred twenty thousand, six hundred forty-three".