13004640 has 144 divisors (see below), whose sum is σ = 48471696. Its totient is φ = 3148800.

The previous prime is 13004639. The next prime is 13004647. The reversal of 13004640 is 4640031.

13004640 = 459² + 460² + ... + 513².

13004640 is digitally balanced in base 2 and base 4, because in such bases 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 (144).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13004647) 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, 15430 + ... + 16250.

It is an arithmetic number, because the mean of its divisors is an integer number (336609).

Almost surely, 2^13004640 is an apocalyptic number.

13004640 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 13004640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24235848).

13004640 is an abundant number, since it is smaller than the sum of its proper divisors (35467056).

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

13004640 is a wasteful number, since it uses less digits than its factorization.

13004640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853 (or 842 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 13004640 is about 3606.1946702861. The cubic root of 13004640 is about 235.1614402982.

Adding to 13004640 its reverse (4640031), we get a palindrome (17644671).

The spelling of 13004640 in words is "thirteen million, four thousand, six hundred forty".