6646537 has 4 divisors (see below), whose sum is σ = 6715156. Its totient is φ = 6577920.

The previous prime is 6646513. The next prime is 6646543. The reversal of 6646537 is 7356466.

It is the 1053-rd star number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5148361 + 1498176 = 2269^2 + 1224^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6646537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6646496 and 6646505.

It is not an unprimeable number, because it can be changed into a prime (6646837) 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 3 ways as a sum of consecutive naturals, for example, 34164 + ... + 34357.

It is an arithmetic number, because the mean of its divisors is an integer number (1678789).

Almost surely, 2^6646537 is an apocalyptic number.

It is an amenable number.

6646537 is a deficient number, since it is larger than the sum of its proper divisors (68619).

6646537 is an equidigital number, since it uses as much as digits as its factorization.

6646537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68618.

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

The square root of 6646537 is about 2578.0878573082. The cubic root of 6646537 is about 188.0175873844.

The spelling of 6646537 in words is "six million, six hundred forty-six thousand, five hundred thirty-seven".