1662666665 has 16 divisors (see below), whose sum is σ = 2271217536. Its totient is φ = 1156636800.

The previous prime is 1662666653. The next prime is 1662666671. The reversal of 1662666665 is 5666662661.

It is not a de Polignac number, because 1662666665 - 2⁸ = 1662666409 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 655916 + ... + 658445.

It is an arithmetic number, because the mean of its divisors is an integer number (141951096).

Almost surely, 2^1662666665 is an apocalyptic number.

It is an amenable number.

1662666665 is a deficient number, since it is larger than the sum of its proper divisors (608550871).

1662666665 is a wasteful number, since it uses less digits than its factorization.

1662666665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1314400.

The product of its digits is 2799360, while the sum is 50.

The square root of 1662666665 is about 40775.8098018911. The cubic root of 1662666665 is about 1184.6818364024.

The spelling of 1662666665 in words is "one billion, six hundred sixty-two million, six hundred sixty-six thousand, six hundred sixty-five".