13221020 has 24 divisors (see below), whose sum is σ = 27917568. Its totient is φ = 5259200.

The previous prime is 13221011. The next prime is 13221029. The reversal of 13221020 is 2012231.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (13221011) and next prime (13221029).

It is a junction number, because it is equal to n+sod(n) for n = 13220992 and 13221010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13221029) 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 7 ways as a sum of consecutive naturals, for example, 2090 + ... + 5550.

It is an arithmetic number, because the mean of its divisors is an integer number (1163232).

Almost surely, 2^13221020 is an apocalyptic number.

13221020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13221020 is an abundant number, since it is smaller than the sum of its proper divisors (14696548).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13221020 is a wasteful number, since it uses less digits than its factorization.

13221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3661 (or 3659 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 13221020 is about 3636.0720564917. The cubic root of 13221020 is about 236.4585311096.

Adding to 13221020 its reverse (2012231), we get a palindrome (15233251).

The spelling of 13221020 in words is "thirteen million, two hundred twenty-one thousand, twenty".