1521065521 has 2 divisors, whose sum is σ = 1521065522. Its totient is φ = 1521065520.

The previous prime is 1521065503. The next prime is 1521065563. The reversal of 1521065521 is 1255601251.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 814303296 + 706762225 = 28536^2 + 26585^2 .

It is a cyclic number.

It is not a de Polignac number, because 1521065521 - 2⁷ = 1521065393 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1521065521.

It is not a weakly prime, because it can be changed into another prime (1521065621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 760532760 + 760532761.

It is an arithmetic number, because the mean of its divisors is an integer number (760532761).

Almost surely, 2^1521065521 is an apocalyptic number.

It is an amenable number.

1521065521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1521065521 is an equidigital number, since it uses as much as digits as its factorization.

1521065521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3000, while the sum is 28.

The square root of 1521065521 is about 39000.8400037743. The cubic root of 1521065521 is about 1150.0480184108.

Adding to 1521065521 its reverse (1255601251), we get a palindrome (2776666772).

The spelling of 1521065521 in words is "one billion, five hundred twenty-one million, sixty-five thousand, five hundred twenty-one".