1205643320325 has 18 divisors (see below), whose sum is σ = 2159441147474. Its totient is φ = 643009770720.

The previous prime is 1205643320309. The next prime is 1205643320351. The reversal of 1205643320325 is 5230233465021.

1205643320325 is a `hidden beast` number, since 1 + 2 + 0 + 5 + 6 + 4 + 3 + 320 + 325 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 311183234244 + 894460086081 = 557838^2 + 945759^2 .

It is not a de Polignac number, because 1205643320325 - 2⁴ = 1205643320309 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 1205643320325.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2679207154 + ... + 2679207603.

Almost surely, 2^{1205643320325} is an apocalyptic number.

1205643320325 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1205643320325 is a deficient number, since it is larger than the sum of its proper divisors (953797827149).

1205643320325 is a wasteful number, since it uses less digits than its factorization.

1205643320325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5358414773 (or 5358414765 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 36.

Adding to 1205643320325 its reverse (5230233465021), we get a palindrome (6435876785346).

The spelling of 1205643320325 in words is "one trillion, two hundred five billion, six hundred forty-three million, three hundred twenty thousand, three hundred twenty-five".