31403120731 has 2 divisors, whose sum is σ = 31403120732. Its totient is φ = 31403120730.

The previous prime is 31403120627. The next prime is 31403120747. The reversal of 31403120731 is 13702130413.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31403120731 - 2⁷ = 31403120603 is a prime.

It is a super-2 number, since 2×31403120731² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31403120696 and 31403120705.

It is not a weakly prime, because it can be changed into another prime (31403120531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15701560365 + 15701560366.

It is an arithmetic number, because the mean of its divisors is an integer number (15701560366).

Almost surely, 2^31403120731 is an apocalyptic number.

31403120731 is a deficient number, since it is larger than the sum of its proper divisors (1).

31403120731 is an equidigital number, since it uses as much as digits as its factorization.

31403120731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 25.

The spelling of 31403120731 in words is "thirty-one billion, four hundred three million, one hundred twenty thousand, seven hundred thirty-one".