31751905109 has 2 divisors, whose sum is σ = 31751905110. Its totient is φ = 31751905108.

The previous prime is 31751905063. The next prime is 31751905169. The reversal of 31751905109 is 90150915713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28881303025 + 2870602084 = 169945^2 + 53578^2 .

It is a cyclic number.

It is not a de Polignac number, because 31751905109 - 2²⁸ = 31483469653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31751905169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15875952554 + 15875952555.

It is an arithmetic number, because the mean of its divisors is an integer number (15875952555).

Almost surely, 2^31751905109 is an apocalyptic number.

It is an amenable number.

31751905109 is a deficient number, since it is larger than the sum of its proper divisors (1).

31751905109 is an equidigital number, since it uses as much as digits as its factorization.

31751905109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 42525, while the sum is 41.

The spelling of 31751905109 in words is "thirty-one billion, seven hundred fifty-one million, nine hundred five thousand, one hundred nine".