1662505665 has 64 divisors (see below), whose sum is σ = 2879815680. Its totient is φ = 816583680.

The previous prime is 1662505609. The next prime is 1662505709. The reversal of 1662505665 is 5665052661.

It is not a de Polignac number, because 1662505665 - 2⁸ = 1662505409 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3839289 + ... + 3839721.

It is an arithmetic number, because the mean of its divisors is an integer number (44997120).

Almost surely, 2^1662505665 is an apocalyptic number.

1662505665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1662505665 is a deficient number, since it is larger than the sum of its proper divisors (1217310015).

1662505665 is a wasteful number, since it uses less digits than its factorization.

1662505665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 854.

The product of its (nonzero) digits is 324000, while the sum is 42.

The square root of 1662505665 is about 40773.8355443782. The cubic root of 1662505665 is about 1184.6435966404.

The spelling of 1662505665 in words is "one billion, six hundred sixty-two million, five hundred five thousand, six hundred sixty-five".