1688559191690 has 64 divisors (see below), whose sum is σ = 3627941819904. Its totient is φ = 553258134528.

The previous prime is 1688559191681. The next prime is 1688559191699. The reversal of 1688559191690 is 961919558861.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1688559191681) and next prime (1688559191699).

It is a super-2 number, since 2×1688559191690² (a number of 25 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (68) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 1688559191690.

It is not an unprimeable number, because it can be changed into a prime (1688559191699) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1288142 + ... + 2244198.

It is an arithmetic number, because the mean of its divisors is an integer number (56686590936).

Almost surely, 2^{1688559191690} is an apocalyptic number.

1688559191690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1688559191690 is an abundant number, since it is smaller than the sum of its proper divisors (1939382628214).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1688559191690 is a wasteful number, since it uses less digits than its factorization.

1688559191690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 957191.

The product of its (nonzero) digits is 41990400, while the sum is 68.

The spelling of 1688559191690 in words is "one trillion, six hundred eighty-eight billion, five hundred fifty-nine million, one hundred ninety-one thousand, six hundred ninety".