521648409025 has 6 divisors (see below), whose sum is σ = 646844027222. Its totient is φ = 417318727200.

The previous prime is 521648408977. The next prime is 521648409049. The reversal of 521648409025 is 520904846125.

It can be written as a sum of positive squares in 3 ways, for example, as 839376784 + 520809032241 = 28972^2 + 721671^2 .

It is not a de Polignac number, because 521648409025 - 2⁹ = 521648408513 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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, 10432968156 + ... + 10432968205.

Almost surely, 2^521648409025 is an apocalyptic number.

It is an amenable number.

521648409025 is a deficient number, since it is larger than the sum of its proper divisors (125195618197).

521648409025 is a wasteful number, since it uses less digits than its factorization.

521648409025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20865936371 (or 20865936366 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 46.

The spelling of 521648409025 in words is "five hundred twenty-one billion, six hundred forty-eight million, four hundred nine thousand, twenty-five".