1660565997 has 6 divisors (see below), whose sum is σ = 2398595342. Its totient is φ = 1107043992.

The previous prime is 1660565987. The next prime is 1660565999. The reversal of 1660565997 is 7995650661.

1660565997 is a `hidden beast` number, since 16 + 60 + 565 + 9 + 9 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1466966601 + 193599396 = 38301^2 + 13914^2 .

It is not a de Polignac number, because 1660565997 - 2⁴ = 1660565981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1660565999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92253658 + ... + 92253675.

Almost surely, 2^1660565997 is an apocalyptic number.

It is an amenable number.

1660565997 is a deficient number, since it is larger than the sum of its proper divisors (738029345).

1660565997 is a wasteful number, since it uses less digits than its factorization.

1660565997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184507339 (or 184507336 counting only the distinct ones).

The product of its (nonzero) digits is 3061800, while the sum is 54.

The square root of 1660565997 is about 40750.0429079529. The cubic root of 1660565997 is about 1184.1827040783.

The spelling of 1660565997 in words is "one billion, six hundred sixty million, five hundred sixty-five thousand, nine hundred ninety-seven".