13220353440 has 480 divisors, whose sum is σ = 54578240640. Its totient is φ = 2950649856.

The previous prime is 13220353409. The next prime is 13220353451. The reversal of 13220353440 is 4435302231.

13220353440 is a `hidden beast` number, since 13 + 2 + 203 + 5 + 3 + 440 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

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

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3899266 + ... + 3902654.

It is an arithmetic number, because the mean of its divisors is an integer number (113704668).

Almost surely, 2^13220353440 is an apocalyptic number.

13220353440 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 13220353440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27289120320).

13220353440 is an abundant number, since it is smaller than the sum of its proper divisors (41357887200).

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

13220353440 is a wasteful number, since it uses less digits than its factorization.

13220353440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3466 (or 3449 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 27.

Adding to 13220353440 its reverse (4435302231), we get a palindrome (17655655671).

The spelling of 13220353440 in words is "thirteen billion, two hundred twenty million, three hundred fifty-three thousand, four hundred forty".