13905840 has 80 divisors (see below), whose sum is σ = 46434528. Its totient is φ = 3422208.

The previous prime is 13905833. The next prime is 13905841. The reversal of 13905840 is 4850931.

13905840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×13905840² = 386744772211200, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 13905798 and 13905807.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13905841) 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, 892 + ... + 5348.

Almost surely, 2^13905840 is an apocalyptic number.

13905840 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 13905840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23217264).

13905840 is an abundant number, since it is smaller than the sum of its proper divisors (32528688).

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

13905840 is a wasteful number, since it uses less digits than its factorization.

13905840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4486 (or 4480 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 13905840 is about 3729.0534992140. The cubic root of 13905840 is about 240.4726795584.

The spelling of 13905840 in words is "thirteen million, nine hundred five thousand, eight hundred forty".