1666744159 has 16 divisors (see below), whose sum is σ = 1732816800. Its totient is φ = 1602147456.

The previous prime is 1666744139. The next prime is 1666744169. The reversal of 1666744159 is 9514476661.

It is a cyclic number.

It is not a de Polignac number, because 1666744159 - 2⁷ = 1666744031 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 (1666744139) 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, 1165657 + ... + 1167085.

It is an arithmetic number, because the mean of its divisors is an integer number (108301050).

Almost surely, 2^1666744159 is an apocalyptic number.

1666744159 is a deficient number, since it is larger than the sum of its proper divisors (66072641).

1666744159 is a wasteful number, since it uses less digits than its factorization.

1666744159 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1914.

The product of its digits is 1088640, while the sum is 49.

The square root of 1666744159 is about 40825.7781187328. The cubic root of 1666744159 is about 1185.6494766760.

The spelling of 1666744159 in words is "one billion, six hundred sixty-six million, seven hundred forty-four thousand, one hundred fifty-nine".