1659023856961 has 9 divisors (see below), whose sum is σ = 1663113090531. Its totient is φ = 1654944662784.

The previous prime is 1659023856953. The next prime is 1659023857027. The reversal of 1659023856961 is 1696583209561.

The square root of 1659023856961 is 1288031.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 59911863361 + 1599111993600 = 244769^2 + 1264560^2 .

It is not a de Polignac number, because 1659023856961 - 2³ = 1659023856953 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1659023856961.

It is not an unprimeable number, because it can be changed into a prime (1659023856361) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 616965505 + ... + 616968193.

Almost surely, 2^{1659023856961} is an apocalyptic number.

1659023856961 is the 1288031-st square number.

1659023856961 is the 644016-th centered octagonal number.

It is an amenable number.

1659023856961 is a deficient number, since it is larger than the sum of its proper divisors (4089233570).

1659023856961 is an frugal number, since it uses more digits than its factorization.

1659023856961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6336 (or 3168 counting only the distinct ones).

The product of its (nonzero) digits is 20995200, while the sum is 61.

The spelling of 1659023856961 in words is "one trillion, six hundred fifty-nine billion, twenty-three million, eight hundred fifty-six thousand, nine hundred sixty-one".