13121920 has 128 divisors (see below), whose sum is σ = 37454400. Its totient is φ = 4300800.

The previous prime is 13121887. The next prime is 13121921. The reversal of 13121920 is 2912131.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 129870 + ... + 129970.

Almost surely, 2^13121920 is an apocalyptic number.

13121920 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 13121920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18727200).

13121920 is an abundant number, since it is smaller than the sum of its proper divisors (24332480).

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

13121920 is a wasteful number, since it uses less digits than its factorization.

13121920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 13121920 is about 3622.4190812218. The cubic root of 13121920 is about 235.8662461470.

It can be divided in two parts, 13121 and 920, that added together give a palindrome (14041).

The spelling of 13121920 in words is "thirteen million, one hundred twenty-one thousand, nine hundred twenty".