6657643 has 4 divisors (see below), whose sum is σ = 6662920. Its totient is φ = 6652368.

The previous prime is 6657631. The next prime is 6657661. The reversal of 6657643 is 3467566.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 6657643 - 2¹⁷ = 6526571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6657613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 496 + ... + 3682.

It is an arithmetic number, because the mean of its divisors is an integer number (1665730).

Almost surely, 2^6657643 is an apocalyptic number.

6657643 is a deficient number, since it is larger than the sum of its proper divisors (5277).

6657643 is a wasteful number, since it uses less digits than its factorization.

6657643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5276.

The product of its digits is 90720, while the sum is 37.

The square root of 6657643 is about 2580.2408802280. The cubic root of 6657643 is about 188.1222514802.

The spelling of 6657643 in words is "six million, six hundred fifty-seven thousand, six hundred forty-three".