13939840 has 64 divisors (see below), whose sum is σ = 34810560. Its totient is φ = 5327872.

The previous prime is 13939837. The next prime is 13939859. The reversal of 13939840 is 4893931.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-3 number, since 3×13939840³ (a number of 22 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 13939840.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14247 + ... + 15193.

It is an arithmetic number, because the mean of its divisors is an integer number (543915).

Almost surely, 2^13939840 is an apocalyptic number.

13939840 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 13939840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17405280).

13939840 is an abundant number, since it is smaller than the sum of its proper divisors (20870720).

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

13939840 is an equidigital number, since it uses as much as digits as its factorization.

13939840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 989 (or 977 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 13939840 is about 3733.6095135941. The cubic root of 13939840 is about 240.6685065539.

The spelling of 13939840 in words is "thirteen million, nine hundred thirty-nine thousand, eight hundred forty".