1666260513 has 12 divisors (see below), whose sum is σ = 2415771540. Its totient is φ = 1106709216.

The previous prime is 1666260503. The next prime is 1666260517. The reversal of 1666260513 is 3150626661.

It can be written as a sum of positive squares in 2 ways, for example, as 492307344 + 1173953169 = 22188^2 + 34263^2 .

It is not a de Polignac number, because 1666260513 - 2²⁸ = 1397825057 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1666260517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 341706 + ... + 346547.

It is an arithmetic number, because the mean of its divisors is an integer number (201314295).

Almost surely, 2^1666260513 is an apocalyptic number.

It is an amenable number.

1666260513 is a deficient number, since it is larger than the sum of its proper divisors (749511027).

1666260513 is a wasteful number, since it uses less digits than its factorization.

1666260513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688528 (or 688525 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 1666260513 is about 40819.8543970946. The cubic root of 1666260513 is about 1185.5347839885.

The spelling of 1666260513 in words is "one billion, six hundred sixty-six million, two hundred sixty thousand, five hundred thirteen".