13538820 has 48 divisors (see below), whose sum is σ = 38723328. Its totient is φ = 3532800.

The previous prime is 13538813. The next prime is 13538821. The reversal of 13538820 is 2883531.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (13538821) 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, 420 + ... + 5220.

It is an arithmetic number, because the mean of its divisors is an integer number (806736).

Almost surely, 2^13538820 is an apocalyptic number.

13538820 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 13538820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19361664).

13538820 is an abundant number, since it is smaller than the sum of its proper divisors (25184508).

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

13538820 is a wasteful number, since it uses less digits than its factorization.

13538820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4860 (or 4858 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 13538820 is about 3679.5135548059. The cubic root of 13538820 is about 238.3381723742.

The spelling of 13538820 in words is "thirteen million, five hundred thirty-eight thousand, eight hundred twenty".