6660405 has 24 divisors (see below), whose sum is σ = 11607648. Its totient is φ = 3532896.

The previous prime is 6660397. The next prime is 6660419. The reversal of 6660405 is 5040666.

It is not a de Polignac number, because 6660405 - 2³ = 6660397 is a prime.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 12474 + ... + 12996.

It is an arithmetic number, because the mean of its divisors is an integer number (483652).

Almost surely, 2^6660405 is an apocalyptic number.

It is an amenable number.

6660405 is a deficient number, since it is larger than the sum of its proper divisors (4947243).

6660405 is a wasteful number, since it uses less digits than its factorization.

6660405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 817 (or 814 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 6660405 is about 2580.7760460761. The cubic root of 6660405 is about 188.1482627789.

The spelling of 6660405 in words is "six million, six hundred sixty thousand, four hundred five".