13879840 has 48 divisors (see below), whose sum is σ = 35318808. Its totient is φ = 5124096.

The previous prime is 13879829. The next prime is 13879849. The reversal of 13879840 is 4897831.

It can be written as a sum of positive squares in 4 ways, for example, as 4613904 + 9265936 = 2148^2 + 3044^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 13879793 and 13879802.

It is not an unprimeable number, because it can be changed into a prime (13879849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1257 + ... + 5416.

Almost surely, 2^13879840 is an apocalyptic number.

13879840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13879840 is an abundant number, since it is smaller than the sum of its proper divisors (21438968).

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

13879840 is a wasteful number, since it uses less digits than its factorization.

13879840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6701 (or 6693 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 40.

The square root of 13879840 is about 3725.5657288525. The cubic root of 13879840 is about 240.3227140189.

Subtracting from 13879840 its reverse (4897831), we obtain a square (8982009 = 2997²).

The spelling of 13879840 in words is "thirteen million, eight hundred seventy-nine thousand, eight hundred forty".