687149427917 has 2 divisors, whose sum is σ = 687149427918. Its totient is φ = 687149427916.

The previous prime is 687149427889. The next prime is 687149427953. The reversal of 687149427917 is 719724941786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 676521055081 + 10628372836 = 822509^2 + 103094^2 .

It is a cyclic number.

It is not a de Polignac number, because 687149427917 - 2¹⁰ = 687149426893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687149427967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343574713958 + 343574713959.

It is an arithmetic number, because the mean of its divisors is an integer number (343574713959).

Almost surely, 2^687149427917 is an apocalyptic number.

It is an amenable number.

687149427917 is a deficient number, since it is larger than the sum of its proper divisors (1).

687149427917 is an equidigital number, since it uses as much as digits as its factorization.

687149427917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42674688, while the sum is 65.

The spelling of 687149427917 in words is "six hundred eighty-seven billion, one hundred forty-nine million, four hundred twenty-seven thousand, nine hundred seventeen".