1666629040389 has 4 divisors (see below), whose sum is σ = 2222172053856. Its totient is φ = 1111086026924.

The previous prime is 1666629040369. The next prime is 1666629040411. The reversal of 1666629040389 is 9830409266661.

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 1666629040389 - 2¹⁷ = 1666628909317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666629040339) 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 3 ways as a sum of consecutive naturals, for example, 277771506729 + ... + 277771506734.

It is an arithmetic number, because the mean of its divisors is an integer number (555543013464).

Almost surely, 2^{1666629040389} is an apocalyptic number.

It is an amenable number.

1666629040389 is a deficient number, since it is larger than the sum of its proper divisors (555543013467).

1666629040389 is an equidigital number, since it uses as much as digits as its factorization.

1666629040389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 555543013466.

The product of its (nonzero) digits is 20155392, while the sum is 60.

The spelling of 1666629040389 in words is "one trillion, six hundred sixty-six billion, six hundred twenty-nine million, forty thousand, three hundred eighty-nine".