6661217 has 2 divisors, whose sum is σ = 6661218. Its totient is φ = 6661216.

The previous prime is 6661211. The next prime is 6661223. The reversal of 6661217 is 7121666.

It is a balanced prime because it is at equal distance from previous prime (6661211) and next prime (6661223).

It can be written as a sum of positive squares in only one way, i.e., 4999696 + 1661521 = 2236^2 + 1289^2 .

It is a cyclic number.

It is not a de Polignac number, because 6661217 - 2¹⁰ = 6660193 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6661217.

It is not a weakly prime, because it can be changed into another prime (6661211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3330608 + 3330609.

It is an arithmetic number, because the mean of its divisors is an integer number (3330609).

Almost surely, 2^6661217 is an apocalyptic number.

It is an amenable number.

6661217 is a deficient number, since it is larger than the sum of its proper divisors (1).

6661217 is an equidigital number, since it uses as much as digits as its factorization.

6661217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 29.

The square root of 6661217 is about 2580.9333583028. The cubic root of 6661217 is about 188.1559084692.

The spelling of 6661217 in words is "six million, six hundred sixty-one thousand, two hundred seventeen".