31131129109 has 2 divisors, whose sum is σ = 31131129110. Its totient is φ = 31131129108.

The previous prime is 31131129077. The next prime is 31131129131. The reversal of 31131129109 is 90192113113.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26584324209 + 4546804900 = 163047^2 + 67430^2 .

It is a cyclic number.

It is not a de Polignac number, because 31131129109 - 2⁵ = 31131129077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31131120109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15565564554 + 15565564555.

It is an arithmetic number, because the mean of its divisors is an integer number (15565564555).

Almost surely, 2^31131129109 is an apocalyptic number.

It is an amenable number.

31131129109 is a deficient number, since it is larger than the sum of its proper divisors (1).

31131129109 is an equidigital number, since it uses as much as digits as its factorization.

31131129109 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 31.

The spelling of 31131129109 in words is "thirty-one billion, one hundred thirty-one million, one hundred twenty-nine thousand, one hundred nine".