20320051 has 4 divisors (see below), whose sum is σ = 20815704. Its totient is φ = 19824400.

The previous prime is 20320043. The next prime is 20320057. The reversal of 20320051 is 15002302.

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

It is a cyclic number.

It is not a de Polignac number, because 20320051 - 2³ = 20320043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20320057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 247765 + ... + 247846.

It is an arithmetic number, because the mean of its divisors is an integer number (5203926).

Almost surely, 2^20320051 is an apocalyptic number.

20320051 is a deficient number, since it is larger than the sum of its proper divisors (495653).

20320051 is an equidigital number, since it uses as much as digits as its factorization.

20320051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495652.

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 20320051 is about 4507.7767247281. The cubic root of 20320051 is about 272.8820262491.

Adding to 20320051 its reverse (15002302), we get a palindrome (35322353).

The spelling of 20320051 in words is "twenty million, three hundred twenty thousand, fifty-one".