6509988 has 36 divisors (see below), whose sum is σ = 16707600. Its totient is φ = 2136816.

The previous prime is 6509977. The next prime is 6510011. The reversal of 6509988 is 8899056.

It is a tau number, because it is divible by the number of its divisors (36).

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 11 ways as a sum of consecutive naturals, for example, 1063 + ... + 3761.

It is an arithmetic number, because the mean of its divisors is an integer number (464100).

Almost surely, 2^6509988 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 6509988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8353800).

6509988 is an abundant number, since it is smaller than the sum of its proper divisors (10197612).

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

6509988 is a wasteful number, since it uses less digits than its factorization.

6509988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2776 (or 2771 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 45.

The square root of 6509988 is about 2551.4678128481. The cubic root of 6509988 is about 186.7210994884.

The spelling of 6509988 in words is "six million, five hundred nine thousand, nine hundred eighty-eight".