31730385961 has 2 divisors, whose sum is σ = 31730385962. Its totient is φ = 31730385960.

The previous prime is 31730385959. The next prime is 31730385971. The reversal of 31730385961 is 16958303713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16069365225 + 15661020736 = 126765^2 + 125144^2 .

It is a cyclic number.

It is not a de Polignac number, because 31730385961 - 2¹ = 31730385959 is a prime.

Together with 31730385959, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31730385971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15865192980 + 15865192981.

It is an arithmetic number, because the mean of its divisors is an integer number (15865192981).

Almost surely, 2^31730385961 is an apocalyptic number.

It is an amenable number.

31730385961 is a deficient number, since it is larger than the sum of its proper divisors (1).

31730385961 is an equidigital number, since it uses as much as digits as its factorization.

31730385961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 408240, while the sum is 46.

The spelling of 31730385961 in words is "thirty-one billion, seven hundred thirty million, three hundred eighty-five thousand, nine hundred sixty-one".