523221221521 has 16 divisors (see below), whose sum is σ = 562406016960. Its totient is φ = 484974167040.

The previous prime is 523221221491. The next prime is 523221221531. The reversal of 523221221521 is 125122122325.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-523221221521 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 523221221521.

It is not an unprimeable number, because it can be changed into a prime (523221221531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4751001 + ... + 4859881.

It is an arithmetic number, because the mean of its divisors is an integer number (35150376060).

Almost surely, 2^523221221521 is an apocalyptic number.

It is an amenable number.

523221221521 is a deficient number, since it is larger than the sum of its proper divisors (39184795439).

523221221521 is a wasteful number, since it uses less digits than its factorization.

523221221521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113184.

The product of its digits is 4800, while the sum is 28.

Adding to 523221221521 its reverse (125122122325), we get a palindrome (648343343846).

The spelling of 523221221521 in words is "five hundred twenty-three billion, two hundred twenty-one million, two hundred twenty-one thousand, five hundred twenty-one".