1688635206871 has 2 divisors, whose sum is σ = 1688635206872. Its totient is φ = 1688635206870.

The previous prime is 1688635206847. The next prime is 1688635206883. The reversal of 1688635206871 is 1786025368861.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1688635206871 is a prime.

It is a super-2 number, since 2×1688635206871² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1688635206821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844317603435 + 844317603436.

It is an arithmetic number, because the mean of its divisors is an integer number (844317603436).

Almost surely, 2^{1688635206871} is an apocalyptic number.

1688635206871 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688635206871 is an equidigital number, since it uses as much as digits as its factorization.

1688635206871 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23224320, while the sum is 61.

The spelling of 1688635206871 in words is "one trillion, six hundred eighty-eight billion, six hundred thirty-five million, two hundred six thousand, eight hundred seventy-one".