6621009 has 8 divisors (see below), whose sum is σ = 8906592. Its totient is φ = 4374720.

The previous prime is 6620981. The next prime is 6621029. The reversal of 6621009 is 9001266.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6621009 - 2¹⁹ = 6096721 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6621009.

It is not an unprimeable number, because it can be changed into a prime (6621029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9427 + ... + 10104.

It is an arithmetic number, because the mean of its divisors is an integer number (1113324).

Almost surely, 2^6621009 is an apocalyptic number.

It is an amenable number.

6621009 is a deficient number, since it is larger than the sum of its proper divisors (2285583).

6621009 is a wasteful number, since it uses less digits than its factorization.

6621009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19647.

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 6621009 is about 2573.1321380761. The cubic root of 6621009 is about 187.7765660814.

The spelling of 6621009 in words is "six million, six hundred twenty-one thousand, nine".