6539940 has 120 divisors (see below), whose sum is σ = 22442112. Its totient is φ = 1581120.

The previous prime is 6539927. The next prime is 6539957. The reversal of 6539940 is 499356.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 6539895 and 6539904.

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 39 ways as a sum of consecutive naturals, for example, 17637 + ... + 18003.

Almost surely, 2^6539940 is an apocalyptic number.

6539940 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 6539940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11221056).

6539940 is an abundant number, since it is smaller than the sum of its proper divisors (15902172).

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

6539940 is a wasteful number, since it uses less digits than its factorization.

6539940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 36.

The square root of 6539940 is about 2557.3306395537. The cubic root of 6539940 is about 187.0070250061.

The spelling of 6539940 in words is "six million, five hundred thirty-nine thousand, nine hundred forty".