531243355221 has 12 divisors (see below), whose sum is σ = 795771939872. Its totient is φ = 354162236652.

The previous prime is 531243355211. The next prime is 531243355231. The reversal of 531243355221 is 122553342135.

531243355221 is a `hidden beast` number, since 5 + 3 + 124 + 3 + 3 + 5 + 522 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (531243355211) and next prime (531243355231).

It is not a de Polignac number, because 531243355221 - 2⁵ = 531243355189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (531243355211) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 1093093081 + ... + 1093093566.

Almost surely, 2^531243355221 is an apocalyptic number.

It is an amenable number.

531243355221 is a deficient number, since it is larger than the sum of its proper divisors (264528584651).

531243355221 is an equidigital number, since it uses as much as digits as its factorization.

531243355221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2186186662 (or 2186186650 counting only the distinct ones).

The product of its digits is 108000, while the sum is 36.

Adding to 531243355221 its reverse (122553342135), we get a palindrome (653796697356).

The spelling of 531243355221 in words is "five hundred thirty-one billion, two hundred forty-three million, three hundred fifty-five thousand, two hundred twenty-one".