6403540 has 48 divisors (see below), whose sum is σ = 15805440. Its totient is φ = 2148480.

The previous prime is 6403511. The next prime is 6403571. The reversal of 6403540 is 453046.

6403540 = T₁₉₂ + T₁₉₃ + ... + T₃₅₆.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1741 + ... + 3979.

It is an arithmetic number, because the mean of its divisors is an integer number (329280).

Almost surely, 2^6403540 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6403540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7902720).

6403540 is an abundant number, since it is smaller than the sum of its proper divisors (9401900).

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

6403540 is a wasteful number, since it uses less digits than its factorization.

6403540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2272 (or 2270 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 6403540 is about 2530.5216853447. The cubic root of 6403540 is about 185.6977787526.

Adding to 6403540 its reverse (453046), we get a palindrome (6856586).

The spelling of 6403540 in words is "six million, four hundred three thousand, five hundred forty".