985566636657 has 12 divisors (see below), whose sum is σ = 1432663747060. Its totient is φ = 652859427168.

The previous prime is 985566636547. The next prime is 985566636683. The reversal of 985566636657 is 756636665589.

It can be written as a sum of positive squares in 2 ways, for example, as 676118085696 + 309448550961 = 822264^2 + 556281^2 .

It is not a de Polignac number, because 985566636657 - 2¹⁰ = 985566635633 is a prime.

It is a super-2 number, since 2×985566636657² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (985566636157) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 348748282 + ... + 348751107.

Almost surely, 2^985566636657 is an apocalyptic number.

It is an amenable number.

985566636657 is a deficient number, since it is larger than the sum of its proper divisors (447097110403).

985566636657 is a wasteful number, since it uses less digits than its factorization.

985566636657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 697499552 (or 697499549 counting only the distinct ones).

The product of its digits is 1469664000, while the sum is 72.

The spelling of 985566636657 in words is "nine hundred eighty-five billion, five hundred sixty-six million, six hundred thirty-six thousand, six hundred fifty-seven".