31231020313 has 2 divisors, whose sum is σ = 31231020314. Its totient is φ = 31231020312.

The previous prime is 31231020311. The next prime is 31231020319. The reversal of 31231020313 is 31302013213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28443497104 + 2787523209 = 168652^2 + 52797^2 .

It is an emirp because it is prime and its reverse (31302013213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31231020313 - 2¹ = 31231020311 is a prime.

Together with 31231020311, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31231020311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15615510156 + 15615510157.

It is an arithmetic number, because the mean of its divisors is an integer number (15615510157).

Almost surely, 2^31231020313 is an apocalyptic number.

It is an amenable number.

31231020313 is a deficient number, since it is larger than the sum of its proper divisors (1).

31231020313 is an equidigital number, since it uses as much as digits as its factorization.

31231020313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 31231020313 its reverse (31302013213), we get a palindrome (62533033526).

The spelling of 31231020313 in words is "thirty-one billion, two hundred thirty-one million, twenty thousand, three hundred thirteen".