6659820 has 60 divisors (see below), whose sum is σ = 20897184. Its totient is φ = 1775520.

The previous prime is 6659813. The next prime is 6659833. The reversal of 6659820 is 289566.

6659820 is a `hidden beast` number, since 66 + 598 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 436 + ... + 3675.

Almost surely, 2^6659820 is an apocalyptic number.

6659820 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6659820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10448592).

6659820 is an abundant number, since it is smaller than the sum of its proper divisors (14237364).

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

6659820 is a wasteful number, since it uses less digits than its factorization.

6659820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4132 (or 4121 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 6659820 is about 2580.6627055855. The cubic root of 6659820 is about 188.1427541071.

The spelling of 6659820 in words is "six million, six hundred fifty-nine thousand, eight hundred twenty".