13820040 has 96 divisors (see below), whose sum is σ = 48386520. Its totient is φ = 3400704.

The previous prime is 13819991. The next prime is 13820041. The reversal of 13820040 is 4002831.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10771524 + 3048516 = 3282^2 + 1746^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 13819995 and 13820022.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13820041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3204 + ... + 6156.

Almost surely, 2^13820040 is an apocalyptic number.

13820040 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 13820040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24193260).

13820040 is an abundant number, since it is smaller than the sum of its proper divisors (34566480).

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

13820040 is a wasteful number, since it uses less digits than its factorization.

13820040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2983 (or 2976 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 13820040 is about 3717.5314390063. The cubic root of 13820040 is about 239.9770811448.

Adding to 13820040 its reverse (4002831), we get a palindrome (17822871).

The spelling of 13820040 in words is "thirteen million, eight hundred twenty thousand, forty".