306820 has 36 divisors (see below), whose sum is σ = 696780. Its totient is φ = 113344.

The previous prime is 306809. The next prime is 306821. The reversal of 306820 is 28603.

It can be written as a sum of positive squares in 2 ways, for example, as 135424 + 171396 = 368^2 + 414^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (306821) by changing a digit.

306820 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10566 + ... + 10594.

It is an arithmetic number, because the mean of its divisors is an integer number (19355).

2³⁰⁶⁸²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 306820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (348390).

306820 is an abundant number, since it is smaller than the sum of its proper divisors (389960).

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

306820 is a wasteful number, since it uses less digits than its factorization.

306820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 306820 is about 553.9133506244. The cubic root of 306820 is about 67.4467801811.

The spelling of 306820 in words is "three hundred six thousand, eight hundred twenty".