6539820 has 96 divisors (see below), whose sum is σ = 21869568. Its totient is φ = 1427712.

The previous prime is 6539807. The next prime is 6539831. The reversal of 6539820 is 289356.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9322 + ... + 9998.

It is an arithmetic number, because the mean of its divisors is an integer number (227808).

Almost surely, 2^6539820 is an apocalyptic number.

6539820 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 6539820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10934784).

6539820 is an abundant number, since it is smaller than the sum of its proper divisors (15329748).

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

6539820 is a wasteful number, since it uses less digits than its factorization.

6539820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 719 (or 717 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 6539820 is about 2557.3071774818. The cubic root of 6539820 is about 187.0058812147.

The spelling of 6539820 in words is "six million, five hundred thirty-nine thousand, eight hundred twenty".