6521940 has 72 divisors (see below), whose sum is σ = 20835360. Its totient is φ = 1646784.

The previous prime is 6521929. The next prime is 6521947. The reversal of 6521940 is 491256.

6521940 is a `hidden beast` number, since 652 + 1 + 9 + 4 + 0 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6521947) 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, 2467 + ... + 4373.

It is an arithmetic number, because the mean of its divisors is an integer number (289380).

Almost surely, 2^6521940 is an apocalyptic number.

6521940 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 6521940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10417680).

6521940 is an abundant number, since it is smaller than the sum of its proper divisors (14313420).

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

6521940 is a wasteful number, since it uses less digits than its factorization.

6521940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941 (or 1936 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 6521940 is about 2553.8089200251. The cubic root of 6521940 is about 186.8352997100.

The spelling of 6521940 in words is "six million, five hundred twenty-one thousand, nine hundred forty".