521475641421557 has 2 divisors, whose sum is σ = 521475641421558. Its totient is φ = 521475641421556.

The previous prime is 521475641421529. The next prime is 521475641421601. The reversal of 521475641421557 is 755124146574125.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 507353370544036 + 14122270877521 = 22524506^2 + 3757961^2 .

It is a cyclic number.

It is not a de Polignac number, because 521475641421557 - 2¹² = 521475641417461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 521475641421496 and 521475641421505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521475241421557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260737820710778 + 260737820710779.

It is an arithmetic number, because the mean of its divisors is an integer number (260737820710779).

Almost surely, 2^{521475641421557} is an apocalyptic number.

It is an amenable number.

521475641421557 is a deficient number, since it is larger than the sum of its proper divisors (1).

521475641421557 is an equidigital number, since it uses as much as digits as its factorization.

521475641421557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 47040000, while the sum is 59.

The spelling of 521475641421557 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 fifty-seven".