71687938009 has 2 divisors, whose sum is σ = 71687938010. Its totient is φ = 71687938008.

The previous prime is 71687937991. The next prime is 71687938073. The reversal of 71687938009 is 90083978617.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55913331600 + 15774606409 = 236460^2 + 125597^2 .

It is a cyclic number.

It is not a de Polignac number, because 71687938009 - 2²¹ = 71685840857 is a prime.

It is not a weakly prime, because it can be changed into another prime (71687938109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35843969004 + 35843969005.

It is an arithmetic number, because the mean of its divisors is an integer number (35843969005).

Almost surely, 2^71687938009 is an apocalyptic number.

It is an amenable number.

71687938009 is a deficient number, since it is larger than the sum of its proper divisors (1).

71687938009 is an equidigital number, since it uses as much as digits as its factorization.

71687938009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 71687938009 in words is "seventy-one billion, six hundred eighty-seven million, nine hundred thirty-eight thousand, nine".