31726618613 has 2 divisors, whose sum is σ = 31726618614. Its totient is φ = 31726618612.

The previous prime is 31726618597. The next prime is 31726618631. The reversal of 31726618613 is 31681662713.

Together with next prime (31726618631) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24558964369 + 7167654244 = 156713^2 + 84662^2 .

It is a cyclic number.

It is not a de Polignac number, because 31726618613 - 2⁴ = 31726618597 is a prime.

It is a super-2 number, since 2×31726618613² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31726618213) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15863309306 + 15863309307.

It is an arithmetic number, because the mean of its divisors is an integer number (15863309307).

Almost surely, 2^31726618613 is an apocalyptic number.

It is an amenable number.

31726618613 is a deficient number, since it is larger than the sum of its proper divisors (1).

31726618613 is an equidigital number, since it uses as much as digits as its factorization.

31726618613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 44.

The spelling of 31726618613 in words is "thirty-one billion, seven hundred twenty-six million, six hundred eighteen thousand, six hundred thirteen".