13220388 has 48 divisors (see below), whose sum is σ = 34527360. Its totient is φ = 4374432.

The previous prime is 13220387. The next prime is 13220401. The reversal of 13220388 is 88302231.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (13220381) 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 15 ways as a sum of consecutive naturals, for example, 17670 + ... + 18402.

It is an arithmetic number, because the mean of its divisors is an integer number (719320).

Almost surely, 2^13220388 is an apocalyptic number.

13220388 is a gapful number since it is divisible by the number (18) 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 13220388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17263680).

13220388 is an abundant number, since it is smaller than the sum of its proper divisors (21306972).

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

13220388 is a wasteful number, since it uses less digits than its factorization.

13220388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 913 (or 905 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 13220388 is about 3635.9851484845. The cubic root of 13220388 is about 236.4547632669.

The spelling of 13220388 in words is "thirteen million, two hundred twenty thousand, three hundred eighty-eight".