312500531521 has 2 divisors, whose sum is σ = 312500531522. Its totient is φ = 312500531520.

The previous prime is 312500531509. The next prime is 312500531533. The reversal of 312500531521 is 125135005213.

It is a balanced prime because it is at equal distance from previous prime (312500531509) and next prime (312500531533).

It can be written as a sum of positive squares in only one way, i.e., 309315057921 + 3185473600 = 556161^2 + 56440^2 .

It is a cyclic number.

It is not a de Polignac number, because 312500531521 - 2⁵ = 312500531489 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 312500531521.

It is not a weakly prime, because it can be changed into another prime (312500531591) 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 as a sum of consecutive naturals, namely, 156250265760 + 156250265761.

It is an arithmetic number, because the mean of its divisors is an integer number (156250265761).

Almost surely, 2^312500531521 is an apocalyptic number.

It is an amenable number.

312500531521 is a deficient number, since it is larger than the sum of its proper divisors (1).

312500531521 is an equidigital number, since it uses as much as digits as its factorization.

312500531521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4500, while the sum is 28.

Adding to 312500531521 its reverse (125135005213), we get a palindrome (437635536734).

The spelling of 312500531521 in words is "three hundred twelve billion, five hundred million, five hundred thirty-one thousand, five hundred twenty-one".