31123090109 has 2 divisors, whose sum is σ = 31123090110. Its totient is φ = 31123090108.

The previous prime is 31123090007. The next prime is 31123090123. The reversal of 31123090109 is 90109032113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24484425625 + 6638664484 = 156475^2 + 81478^2 .

It is an emirp because it is prime and its reverse (90109032113) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31123090109 - 2⁸ = 31123089853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31123090139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561545054 + 15561545055.

It is an arithmetic number, because the mean of its divisors is an integer number (15561545055).

Almost surely, 2^31123090109 is an apocalyptic number.

It is an amenable number.

31123090109 is a deficient number, since it is larger than the sum of its proper divisors (1).

31123090109 is an equidigital number, since it uses as much as digits as its factorization.

31123090109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1458, while the sum is 29.

The spelling of 31123090109 in words is "thirty-one billion, one hundred twenty-three million, ninety thousand, one hundred nine".