1666717863 has 16 divisors (see below), whose sum is σ = 2252240640. Its totient is φ = 1096225856.

The previous prime is 1666717861. The next prime is 1666717879. The reversal of 1666717863 is 3687176661.

It is a cyclic number.

It is not a de Polignac number, because 1666717863 - 2¹ = 1666717861 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666717861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118006 + ... + 131372.

It is an arithmetic number, because the mean of its divisors is an integer number (140765040).

Almost surely, 2^1666717863 is an apocalyptic number.

1666717863 is a deficient number, since it is larger than the sum of its proper divisors (585522777).

1666717863 is a wasteful number, since it uses less digits than its factorization.

1666717863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13926.

The product of its digits is 1524096, while the sum is 51.

The square root of 1666717863 is about 40825.4560660380. The cubic root of 1666717863 is about 1185.6432413654.

The spelling of 1666717863 in words is "one billion, six hundred sixty-six million, seven hundred seventeen thousand, eight hundred sixty-three".