6611621 has 2 divisors, whose sum is σ = 6611622. Its totient is φ = 6611620.

The previous prime is 6611611. The next prime is 6611629. The reversal of 6611621 is 1261166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6558721 + 52900 = 2561^2 + 230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6611621 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6611629) 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, 3305810 + 3305811.

It is an arithmetic number, because the mean of its divisors is an integer number (3305811).

Almost surely, 2^6611621 is an apocalyptic number.

It is an amenable number.

6611621 is a deficient number, since it is larger than the sum of its proper divisors (1).

6611621 is an equidigital number, since it uses as much as digits as its factorization.

6611621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 23.

The square root of 6611621 is about 2571.3072550747. The cubic root of 6611621 is about 187.6877739630.

Adding to 6611621 its reverse (1261166), we get a palindrome (7872787).

The spelling of 6611621 in words is "six million, six hundred eleven thousand, six hundred twenty-one".