1689666789 has 16 divisors (see below), whose sum is σ = 2372753600. Its totient is φ = 1066576896.

The previous prime is 1689666787. The next prime is 1689666791. The reversal of 1689666789 is 9876669861.

It is an interprime number because it is at equal distance from previous prime (1689666787) and next prime (1689666791).

It is not a de Polignac number, because 1689666789 - 2¹ = 1689666787 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1689666787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 113427 + ... + 127455.

It is an arithmetic number, because the mean of its divisors is an integer number (148297100).

Almost surely, 2^1689666789 is an apocalyptic number.

1689666789 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1689666789 is a deficient number, since it is larger than the sum of its proper divisors (683086811).

1689666789 is a wasteful number, since it uses less digits than its factorization.

1689666789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16164.

The product of its digits is 47029248, while the sum is 66.

The square root of 1689666789 is about 41105.5566681684. The cubic root of 1689666789 is about 1191.0601359432.

The spelling of 1689666789 in words is "one billion, six hundred eighty-nine million, six hundred sixty-six thousand, seven hundred eighty-nine".