1665065644 has 12 divisors (see below), whose sum is σ = 3178761768. Its totient is φ = 756848000.

The previous prime is 1665065639. The next prime is 1665065669. The reversal of 1665065644 is 4465605661.

It is a self number, because there is not a number n which added to its sum of digits gives 1665065644.

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 3 ways as a sum of consecutive naturals, for example, 18921157 + ... + 18921244.

It is an arithmetic number, because the mean of its divisors is an integer number (264896814).

Almost surely, 2^1665065644 is an apocalyptic number.

It is an amenable number.

1665065644 is a deficient number, since it is larger than the sum of its proper divisors (1513696124).

1665065644 is a wasteful number, since it uses less digits than its factorization.

1665065644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37842416 (or 37842414 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 43.

The square root of 1665065644 is about 40805.2158920891. The cubic root of 1665065644 is about 1185.2513354143.

The spelling of 1665065644 in words is "one billion, six hundred sixty-five million, sixty-five thousand, six hundred forty-four".