1688968815 has 16 divisors (see below), whose sum is σ = 2789523456. Its totient is φ = 871725600.

The previous prime is 1688968781. The next prime is 1688968817. The reversal of 1688968815 is 5188698861.

It is not a de Polignac number, because 1688968815 - 2¹¹ = 1688966767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688968817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1815631 + ... + 1816560.

It is an arithmetic number, because the mean of its divisors is an integer number (174345216).

Almost surely, 2^1688968815 is an apocalyptic number.

1688968815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1688968815 is a deficient number, since it is larger than the sum of its proper divisors (1100554641).

1688968815 is a wasteful number, since it uses less digits than its factorization.

1688968815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3632230.

The product of its digits is 6635520, while the sum is 60.

The square root of 1688968815 is about 41097.0657711715. The cubic root of 1688968815 is about 1190.8961108016.

The spelling of 1688968815 in words is "one billion, six hundred eighty-eight million, nine hundred sixty-eight thousand, eight hundred fifteen".