13881720 has 64 divisors (see below), whose sum is σ = 43092000. Its totient is φ = 3573248.

The previous prime is 13881713. The next prime is 13881737. The reversal of 13881720 is 2718831.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1486 + ... + 5474.

Almost surely, 2^13881720 is an apocalyptic number.

13881720 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 13881720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21546000).

13881720 is an abundant number, since it is smaller than the sum of its proper divisors (29210280).

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

13881720 is a wasteful number, since it uses less digits than its factorization.

13881720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4032 (or 4028 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 30.

The square root of 13881720 is about 3725.8180309833. The cubic root of 13881720 is about 240.3335639592. Note that the first 3 decimals are identical.

The spelling of 13881720 in words is "thirteen million, eight hundred eighty-one thousand, seven hundred twenty".