13121320 has 32 divisors (see below), whose sum is σ = 29675520. Its totient is φ = 5221440.

The previous prime is 13121309. The next prime is 13121327. The reversal of 13121320 is 2312131.

It is a self number, because there is not a number n which added to its sum of digits gives 13121320.

It is not an unprimeable number, because it can be changed into a prime (13121327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8185 + ... + 9655.

It is an arithmetic number, because the mean of its divisors is an integer number (927360).

Almost surely, 2^13121320 is an apocalyptic number.

13121320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13121320 is an abundant number, since it is smaller than the sum of its proper divisors (16554200).

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

13121320 is a wasteful number, since it uses less digits than its factorization.

13121320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1705 (or 1701 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 13121320 is about 3622.3362626901. The cubic root of 13121320 is about 235.8626510962.

Adding to 13121320 its reverse (2312131), we get a palindrome (15433451).

The spelling of 13121320 in words is "thirteen million, one hundred twenty-one thousand, three hundred twenty".