6620409 has 12 divisors (see below), whose sum is σ = 9785776. Its totient is φ = 4310712.

The previous prime is 6620407. The next prime is 6620423. The reversal of 6620409 is 9040266.

It is not a de Polignac number, because 6620409 - 2¹ = 6620407 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6620401) by changing a digit.

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, 8167 + ... + 8940.

Almost surely, 2^6620409 is an apocalyptic number.

It is an amenable number.

6620409 is a deficient number, since it is larger than the sum of its proper divisors (3165367).

6620409 is a wasteful number, since it uses less digits than its factorization.

6620409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17156 (or 17153 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 6620409 is about 2573.0155460082. The cubic root of 6620409 is about 187.7708937665.

The spelling of 6620409 in words is "six million, six hundred twenty thousand, four hundred nine".