646353202025 has 6 divisors (see below), whose sum is σ = 801477970542. Its totient is φ = 517082561600.

The previous prime is 646353202009. The next prime is 646353202043. The reversal of 646353202025 is 520202353646.

It can be written as a sum of positive squares in 3 ways, for example, as 156091367056 + 490261834969 = 395084^2 + 700187^2 .

It is not a de Polignac number, because 646353202025 - 2⁴ = 646353202009 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 646353202025.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12927064016 + ... + 12927064065.

It is an arithmetic number, because the mean of its divisors is an integer number (133579661757).

Almost surely, 2^646353202025 is an apocalyptic number.

It is an amenable number.

646353202025 is a deficient number, since it is larger than the sum of its proper divisors (155124768517).

646353202025 is a wasteful number, since it uses less digits than its factorization.

646353202025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25854128091 (or 25854128086 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 38.

The spelling of 646353202025 in words is "six hundred forty-six billion, three hundred fifty-three million, two hundred two thousand, twenty-five".