6601728009 has 4 divisors (see below), whose sum is σ = 8802304016. Its totient is φ = 4401152004.

The previous prime is 6601727999. The next prime is 6601728013. The reversal of 6601728009 is 9008271066.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 6601728009 - 2¹² = 6601723913 is a prime.

It is a super-3 number, since 3×6601728009³ (a number of 30 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6601728059) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1100287999 + ... + 1100288004.

It is an arithmetic number, because the mean of its divisors is an integer number (2200576004).

Almost surely, 2^6601728009 is an apocalyptic number.

It is an amenable number.

6601728009 is a deficient number, since it is larger than the sum of its proper divisors (2200576007).

6601728009 is a wasteful number, since it uses less digits than its factorization.

6601728009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2200576006.

The product of its (nonzero) digits is 36288, while the sum is 39.

The square root of 6601728009 is about 81251.0185105393. The cubic root of 6601728009 is about 1875.9411461488.

The spelling of 6601728009 in words is "six billion, six hundred one million, seven hundred twenty-eight thousand, nine".