31131133009 has 2 divisors, whose sum is σ = 31131133010. Its totient is φ = 31131133008.

The previous prime is 31131132997. The next prime is 31131133067. The reversal of 31131133009 is 90033113113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18164300625 + 12966832384 = 134775^2 + 113872^2 .

It is an emirp because it is prime and its reverse (90033113113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31131133009 - 2⁹ = 31131132497 is a prime.

It is not a weakly prime, because it can be changed into another prime (31131133409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565566504 + 15565566505.

It is an arithmetic number, because the mean of its divisors is an integer number (15565566505).

Almost surely, 2^31131133009 is an apocalyptic number.

It is an amenable number.

31131133009 is a deficient number, since it is larger than the sum of its proper divisors (1).

31131133009 is an equidigital number, since it uses as much as digits as its factorization.

31131133009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 729, while the sum is 25.

The spelling of 31131133009 in words is "thirty-one billion, one hundred thirty-one million, one hundred thirty-three thousand, nine".