1666005415 has 16 divisors (see below), whose sum is σ = 2029237056. Its totient is φ = 1312819200.

The previous prime is 1666005409. The next prime is 1666005449. The reversal of 1666005415 is 5145006661.

It is a happy number.

It is not a de Polignac number, because 1666005415 - 2¹⁹ = 1665481127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 749005 + ... + 751225.

It is an arithmetic number, because the mean of its divisors is an integer number (126827316).

Almost surely, 2^1666005415 is an apocalyptic number.

1666005415 is a deficient number, since it is larger than the sum of its proper divisors (363231641).

1666005415 is a wasteful number, since it uses less digits than its factorization.

1666005415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4410.

The product of its (nonzero) digits is 21600, while the sum is 34.

The square root of 1666005415 is about 40816.7295970660. The cubic root of 1666005415 is about 1185.4742806469.

The spelling of 1666005415 in words is "one billion, six hundred sixty-six million, five thousand, four hundred fifteen".