666700480561 has 2 divisors, whose sum is σ = 666700480562. Its totient is φ = 666700480560.

The previous prime is 666700480507. The next prime is 666700480573. The reversal of 666700480561 is 165084007666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 511180670961 + 155519809600 = 714969^2 + 394360^2 .

It is a cyclic number.

It is not a de Polignac number, because 666700480561 - 2²¹ = 666698383409 is a prime.

It is not a weakly prime, because it can be changed into another prime (666700480861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333350240280 + 333350240281.

It is an arithmetic number, because the mean of its divisors is an integer number (333350240281).

Almost surely, 2^666700480561 is an apocalyptic number.

It is an amenable number.

666700480561 is a deficient number, since it is larger than the sum of its proper divisors (1).

666700480561 is an equidigital number, since it uses as much as digits as its factorization.

666700480561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 666700480561 in words is "six hundred sixty-six billion, seven hundred million, four hundred eighty thousand, five hundred sixty-one".