666944461 has 2 divisors, whose sum is σ = 666944462. Its totient is φ = 666944460.

The previous prime is 666944431. The next prime is 666944471. The reversal of 666944461 is 164449666.

666944461 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 556063561 + 110880900 = 23581^2 + 10530^2 .

It is a cyclic number.

It is not a de Polignac number, because 666944461 - 2¹¹ = 666942413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666944431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333472230 + 333472231.

It is an arithmetic number, because the mean of its divisors is an integer number (333472231).

Almost surely, 2^666944461 is an apocalyptic number.

It is an amenable number.

666944461 is a deficient number, since it is larger than the sum of its proper divisors (1).

666944461 is an equidigital number, since it uses as much as digits as its factorization.

666944461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 746496, while the sum is 46.

The square root of 666944461 is about 25825.2678785719. The cubic root of 666944461 is about 873.7017857381.

The spelling of 666944461 in words is "six hundred sixty-six million, nine hundred forty-four thousand, four hundred sixty-one".