1688020 has 12 divisors (see below), whose sum is σ = 3544884. Its totient is φ = 675200.

The previous prime is 1687999. The next prime is 1688041. The reversal of 1688020 is 208861.

It is an interprime number because it is at equal distance from previous prime (1687999) and next prime (1688041).

It can be written as a sum of positive squares in 2 ways, for example, as 276676 + 1411344 = 526^2 + 1188^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42181 + ... + 42220.

It is an arithmetic number, because the mean of its divisors is an integer number (295407).

2^1688020 is an apocalyptic number.

1688020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1688020 is an abundant number, since it is smaller than the sum of its proper divisors (1856864).

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

1688020 is a wasteful number, since it uses less digits than its factorization.

1688020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84410 (or 84408 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 1688020 is about 1299.2382383535. The cubic root of 1688020 is about 119.0673065091.

It can be divided in two parts, 16880 and 20, that added together give a square (16900 = 130²).

The spelling of 1688020 in words is "one million, six hundred eighty-eight thousand, twenty".