1686701686669 has 4 divisors (see below), whose sum is σ = 1696020480700. Its totient is φ = 1677382892640.

The previous prime is 1686701686667. The next prime is 1686701686673. The reversal of 1686701686669 is 9666861076861.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 349759874025 + 1336941812644 = 591405^2 + 1156262^2 .

It is a cyclic number.

It is not a de Polignac number, because 1686701686669 - 2¹ = 1686701686667 is a prime.

It is a super-2 number, since 2×1686701686669² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1686701686598 and 1686701686607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686701686667) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4659396744 + ... + 4659397105.

It is an arithmetic number, because the mean of its divisors is an integer number (424005120175).

Almost surely, 2^{1686701686669} is an apocalyptic number.

It is an amenable number.

1686701686669 is a deficient number, since it is larger than the sum of its proper divisors (9318794031).

1686701686669 is an equidigital number, since it uses as much as digits as its factorization.

1686701686669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9318794030.

The product of its (nonzero) digits is 188116992, while the sum is 70.

The spelling of 1686701686669 in words is "one trillion, six hundred eighty-six billion, seven hundred one million, six hundred eighty-six thousand, six hundred sixty-nine".