20328309 has 24 divisors (see below), whose sum is σ = 31505760. Its totient is φ = 12591072.

The previous prime is 20328307. The next prime is 20328317. The reversal of 20328309 is 90382302.

It is not a de Polignac number, because 20328309 - 2¹ = 20328307 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20328307) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7942 + ... + 10184.

It is an arithmetic number, because the mean of its divisors is an integer number (1312740).

Almost surely, 2^20328309 is an apocalyptic number.

It is an amenable number.

20328309 is a deficient number, since it is larger than the sum of its proper divisors (11177451).

20328309 is a wasteful number, since it uses less digits than its factorization.

20328309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2321 (or 2318 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 20328309 is about 4508.6926042923. The cubic root of 20328309 is about 272.9189873534.

It can be divided in two parts, 20 and 328309, that added together give a square (328329 = 573²).

The spelling of 20328309 in words is "twenty million, three hundred twenty-eight thousand, three hundred nine".