31997182117 has 2 divisors, whose sum is σ = 31997182118. Its totient is φ = 31997182116.

The previous prime is 31997182093. The next prime is 31997182121. The reversal of 31997182117 is 71128179913.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16220314881 + 15776867236 = 127359^2 + 125606^2 .

It is a cyclic number.

It is not a de Polignac number, because 31997182117 - 2¹⁹ = 31996657829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31997182817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15998591058 + 15998591059.

It is an arithmetic number, because the mean of its divisors is an integer number (15998591059).

Almost surely, 2^31997182117 is an apocalyptic number.

It is an amenable number.

31997182117 is a deficient number, since it is larger than the sum of its proper divisors (1).

31997182117 is an equidigital number, since it uses as much as digits as its factorization.

31997182117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 49.

The spelling of 31997182117 in words is "thirty-one billion, nine hundred ninety-seven million, one hundred eighty-two thousand, one hundred seventeen".