6404940 has 96 divisors (see below), whose sum is σ = 20664000. Its totient is φ = 1645056.

The previous prime is 6404929. The next prime is 6404987. The reversal of 6404940 is 494046.

6404940 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15456 + ... + 15864.

It is an arithmetic number, because the mean of its divisors is an integer number (215250).

Almost surely, 2^6404940 is an apocalyptic number.

6404940 is a gapful number since it is divisible by the number (60) 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 6404940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10332000).

6404940 is an abundant number, since it is smaller than the sum of its proper divisors (14259060).

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

6404940 is a wasteful number, since it uses less digits than its factorization.

6404940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456 (or 448 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 6404940 is about 2530.7982930293. The cubic root of 6404940 is about 185.7113107441.

Adding to 6404940 its reverse (494046), we get a palindrome (6898986).

The spelling of 6404940 in words is "six million, four hundred four thousand, nine hundred forty".