20320345 has 12 divisors (see below), whose sum is σ = 25202340. Its totient is φ = 15728160.

The previous prime is 20320343. The next prime is 20320361. The reversal of 20320345 is 54302302.

It can be written as a sum of positive squares in 2 ways, for example, as 15745024 + 4575321 = 3968^2 + 2139^2 .

It is not a de Polignac number, because 20320345 - 2¹ = 20320343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20320343) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2691 + ... + 6919.

It is an arithmetic number, because the mean of its divisors is an integer number (2100195).

Almost surely, 2^20320345 is an apocalyptic number.

It is an amenable number.

20320345 is a deficient number, since it is larger than the sum of its proper divisors (4881995).

20320345 is an equidigital number, since it uses as much as digits as its factorization.

20320345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4296 (or 4265 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 19.

The square root of 20320345 is about 4507.8093349209. The cubic root of 20320345 is about 272.8833423043.

Adding to 20320345 its reverse (54302302), we get a palindrome (74622647).

The spelling of 20320345 in words is "twenty million, three hundred twenty thousand, three hundred forty-five".