6523661 has 2 divisors, whose sum is σ = 6523662. Its totient is φ = 6523660.

The previous prime is 6523619. The next prime is 6523663. The reversal of 6523661 is 1663256.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4818025 + 1705636 = 2195^2 + 1306^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6523661 is a prime.

Together with 6523663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6523663) 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 as a sum of consecutive naturals, namely, 3261830 + 3261831.

It is an arithmetic number, because the mean of its divisors is an integer number (3261831).

Almost surely, 2^6523661 is an apocalyptic number.

It is an amenable number.

6523661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6523661 is an equidigital number, since it uses as much as digits as its factorization.

6523661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 29.

The square root of 6523661 is about 2554.1458454834. The cubic root of 6523661 is about 186.8517322067.

The spelling of 6523661 in words is "six million, five hundred twenty-three thousand, six hundred sixty-one".