521475641421561 has 16 divisors (see below), whose sum is σ = 799196385321600. Its totient is φ = 335662481834064.

The previous prime is 521475641421557. The next prime is 521475641421601. The reversal of 521475641421561 is 165124146574125.

521475641421561 is a `hidden beast` number, since 5 + 2 + 1 + 4 + 7 + 5 + 6 + 414 + 215 + 6 + 1 = 666.

It is not a de Polignac number, because 521475641421561 - 2² = 521475641421557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 521475641421498 and 521475641421507.

It is not an unprimeable number, because it can be changed into a prime (521475641426561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 332998493101 + ... + 332998494666.

It is an arithmetic number, because the mean of its divisors is an integer number (49949774082600).

Almost surely, 2^{521475641421561} is an apocalyptic number.

It is an amenable number.

521475641421561 is a deficient number, since it is larger than the sum of its proper divisors (277720743900039).

521475641421561 is a wasteful number, since it uses less digits than its factorization.

521475641421561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665996987805 (or 665996987799 counting only the distinct ones).

The product of its digits is 8064000, while the sum is 54.

Adding to 521475641421561 its reverse (165124146574125), we get a palindrome (686599787995686).

The spelling of 521475641421561 in words is "five hundred twenty-one trillion, four hundred seventy-five billion, six hundred forty-one million, four hundred twenty-one thousand, five hundred sixty-one".