31520541257 has 2 divisors, whose sum is σ = 31520541258. Its totient is φ = 31520541256.

The previous prime is 31520541251. The next prime is 31520541341. The reversal of 31520541257 is 75214502513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28341385801 + 3179155456 = 168349^2 + 56384^2 .

It is a cyclic number.

It is not a de Polignac number, because 31520541257 - 2¹⁴ = 31520524873 is a prime.

It is a super-2 number, since 2×31520541257² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31520541251) 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, 15760270628 + 15760270629.

It is an arithmetic number, because the mean of its divisors is an integer number (15760270629).

Almost surely, 2^31520541257 is an apocalyptic number.

It is an amenable number.

31520541257 is a deficient number, since it is larger than the sum of its proper divisors (1).

31520541257 is an equidigital number, since it uses as much as digits as its factorization.

31520541257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42000, while the sum is 35.

The spelling of 31520541257 in words is "thirty-one billion, five hundred twenty million, five hundred forty-one thousand, two hundred fifty-seven".