1666945093 has 4 divisors (see below), whose sum is σ = 1818485568. Its totient is φ = 1515404620.

The previous prime is 1666945073. The next prime is 1666945121. The reversal of 1666945093 is 3905496661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1666945093 - 2²¹ = 1664847941 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 (1666945003) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75770221 + ... + 75770242.

It is an arithmetic number, because the mean of its divisors is an integer number (454621392).

Almost surely, 2^1666945093 is an apocalyptic number.

It is an amenable number.

1666945093 is a deficient number, since it is larger than the sum of its proper divisors (151540475).

1666945093 is a wasteful number, since it uses less digits than its factorization.

1666945093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151540474.

The product of its (nonzero) digits is 1049760, while the sum is 49.

The square root of 1666945093 is about 40828.2389162207. The cubic root of 1666945093 is about 1185.6971200046.

The spelling of 1666945093 in words is "one billion, six hundred sixty-six million, nine hundred forty-five thousand, ninety-three".