31145321573 has 2 divisors, whose sum is σ = 31145321574. Its totient is φ = 31145321572.

The previous prime is 31145321507. The next prime is 31145321587. The reversal of 31145321573 is 37512354113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16143481249 + 15001840324 = 127057^2 + 122482^2 .

It is a cyclic number.

It is not a de Polignac number, because 31145321573 - 2¹² = 31145317477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31145321503) 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, 15572660786 + 15572660787.

It is an arithmetic number, because the mean of its divisors is an integer number (15572660787).

Almost surely, 2^31145321573 is an apocalyptic number.

It is an amenable number.

31145321573 is a deficient number, since it is larger than the sum of its proper divisors (1).

31145321573 is an equidigital number, since it uses as much as digits as its factorization.

31145321573 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37800, while the sum is 35.

Adding to 31145321573 its reverse (37512354113), we get a palindrome (68657675686).

The spelling of 31145321573 in words is "thirty-one billion, one hundred forty-five million, three hundred twenty-one thousand, five hundred seventy-three".