31313220321431 has 2 divisors, whose sum is σ = 31313220321432. Its totient is φ = 31313220321430.

The previous prime is 31313220321371. The next prime is 31313220321437. The reversal of 31313220321431 is 13412302231313.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31313220321431 - 2¹⁰ = 31313220320407 is a prime.

It is a super-2 number, since 2×31313220321431² (a number of 28 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31313220321394 and 31313220321403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31313220321437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15656610160715 + 15656610160716.

It is an arithmetic number, because the mean of its divisors is an integer number (15656610160716).

Almost surely, 2^{31313220321431} is an apocalyptic number.

31313220321431 is a deficient number, since it is larger than the sum of its proper divisors (1).

31313220321431 is an equidigital number, since it uses as much as digits as its factorization.

31313220321431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 29.

Adding to 31313220321431 its reverse (13412302231313), we get a palindrome (44725522552744).

The spelling of 31313220321431 in words is "thirty-one trillion, three hundred thirteen billion, two hundred twenty million, three hundred twenty-one thousand, four hundred thirty-one".