1665616564 has 12 divisors (see below), whose sum is σ = 2915323488. Its totient is φ = 832667000.

The previous prime is 1665616559. The next prime is 1665616607. The reversal of 1665616564 is 4656165661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6112 + ... + 58039.

It is an arithmetic number, because the mean of its divisors is an integer number (242943624).

Almost surely, 2^1665616564 is an apocalyptic number.

It is an amenable number.

1665616564 is a deficient number, since it is larger than the sum of its proper divisors (1249706924).

1665616564 is a wasteful number, since it uses less digits than its factorization.

1665616564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70646 (or 70644 counting only the distinct ones).

The product of its digits is 777600, while the sum is 46.

The square root of 1665616564 is about 40811.9659413756. The cubic root of 1665616564 is about 1185.3820423055.

The spelling of 1665616564 in words is "one billion, six hundred sixty-five million, six hundred sixteen thousand, five hundred sixty-four".