1665100665 has 16 divisors (see below), whose sum is σ = 2960179200. Its totient is φ = 888053616.

The previous prime is 1665100639. The next prime is 1665100691. The reversal of 1665100665 is 5660015661.

It is an interprime number because it is at equal distance from previous prime (1665100639) and next prime (1665100691).

It is not a de Polignac number, because 1665100665 - 2⁶ = 1665100601 is a prime.

It is a Curzon 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, 6166905 + ... + 6167174.

It is an arithmetic number, because the mean of its divisors is an integer number (185011200).

Almost surely, 2^1665100665 is an apocalyptic number.

1665100665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1665100665 is a deficient number, since it is larger than the sum of its proper divisors (1295078535).

1665100665 is a wasteful number, since it uses less digits than its factorization.

1665100665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12334093 (or 12334087 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 1665100665 is about 40805.6450138948. The cubic root of 1665100665 is about 1185.2596450759.

The spelling of 1665100665 in words is "one billion, six hundred sixty-five million, one hundred thousand, six hundred sixty-five".