13220720 has 40 divisors (see below), whose sum is σ = 31270320. Its totient is φ = 5196800.

The previous prime is 13220717. The next prime is 13220731. The reversal of 13220720 is 2702231.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

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, 3320 + ... + 6120.

It is an arithmetic number, because the mean of its divisors is an integer number (781758).

Almost surely, 2^13220720 is an apocalyptic number.

13220720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13220720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15635160).

13220720 is an abundant number, since it is smaller than the sum of its proper divisors (18049600).

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

13220720 is a wasteful number, since it uses less digits than its factorization.

13220720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2873 (or 2867 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 17.

The square root of 13220720 is about 3636.0308029498. The cubic root of 13220720 is about 236.4567425916.

Adding to 13220720 its reverse (2702231), we get a palindrome (15922951).

The spelling of 13220720 in words is "thirteen million, two hundred twenty thousand, seven hundred twenty".