2128306 has 4 divisors (see below), whose sum is σ = 3192462. Its totient is φ = 1064152.

The previous prime is 2128303. The next prime is 2128309. The reversal of 2128306 is 6038212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2128303) and next prime (2128309).

It can be written as a sum of positive squares in only one way, i.e., 1625625 + 502681 = 1275^2 + 709^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (2128303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 532075 + ... + 532078.

2^2128306 is an apocalyptic number.

2128306 is a deficient number, since it is larger than the sum of its proper divisors (1064156).

2128306 is a wasteful number, since it uses less digits than its factorization.

2128306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1064155.

The product of its (nonzero) digits is 576, while the sum is 22.

The square root of 2128306 is about 1458.8714816597. The cubic root of 2128306 is about 128.6307168067.

The spelling of 2128306 in words is "two million, one hundred twenty-eight thousand, three hundred six".