13785920 has 56 divisors (see below), whose sum is σ = 33369504. Its totient is φ = 5423616.

The previous prime is 13785913. The next prime is 13785949. The reversal of 13785920 is 2958731.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21119 + ... + 21761.

It is an arithmetic number, because the mean of its divisors is an integer number (595884).

Almost surely, 2^13785920 is an apocalyptic number.

13785920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

13785920 is the 2144-th octagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13785920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16684752).

13785920 is an abundant number, since it is smaller than the sum of its proper divisors (19583584).

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

13785920 is an equidigital number, since it uses as much as digits as its factorization.

13785920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 727 (or 717 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 13785920 is about 3712.9395362704. The cubic root of 13785920 is about 239.7794269731.

The spelling of 13785920 in words is "thirteen million, seven hundred eighty-five thousand, nine hundred twenty".