1666426663 has 8 divisors (see below), whose sum is σ = 1822988160. Its totient is φ = 1510709880.

The previous prime is 1666426639. The next prime is 1666426679. The reversal of 1666426663 is 3666246661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1666426663 - 2⁵ = 1666426631 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666426693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 207045 + ... + 214942.

It is an arithmetic number, because the mean of its divisors is an integer number (227873520).

Almost surely, 2^1666426663 is an apocalyptic number.

1666426663 is a deficient number, since it is larger than the sum of its proper divisors (156561497).

1666426663 is a wasteful number, since it uses less digits than its factorization.

1666426663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422357.

The product of its digits is 1119744, while the sum is 46.

The square root of 1666426663 is about 40821.8895079588. The cubic root of 1666426663 is about 1185.5741876024.

The spelling of 1666426663 in words is "one billion, six hundred sixty-six million, four hundred twenty-six thousand, six hundred sixty-three".