6906661 has 2 divisors, whose sum is σ = 6906662. Its totient is φ = 6906660.

The previous prime is 6906649. The next prime is 6906677. The reversal of 6906661 is 1666096.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5452225 + 1454436 = 2335^2 + 1206^2 .

It is a cyclic number.

It is not a de Polignac number, because 6906661 - 2¹¹ = 6904613 is a prime.

6906661 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6906631) 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, 3453330 + 3453331.

It is an arithmetic number, because the mean of its divisors is an integer number (3453331).

Almost surely, 2^6906661 is an apocalyptic number.

It is an amenable number.

6906661 is a deficient number, since it is larger than the sum of its proper divisors (1).

6906661 is an equidigital number, since it uses as much as digits as its factorization.

6906661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 6906661 is about 2628.0527011459. The cubic root of 6906661 is about 190.4390676871.

The spelling of 6906661 in words is "six million, nine hundred six thousand, six hundred sixty-one".