20003120321 has 4 divisors (see below), whose sum is σ = 20080953732. Its totient is φ = 19925286912.

The previous prime is 20003120317. The next prime is 20003120351. The reversal of 20003120321 is 12302130002.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15052590721 + 4950529600 = 122689^2 + 70360^2 .

It is a cyclic number.

It is not a de Polignac number, because 20003120321 - 2² = 20003120317 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20003120296 and 20003120305.

It is not an unprimeable number, because it can be changed into a prime (20003120351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38916320 + ... + 38916833.

It is an arithmetic number, because the mean of its divisors is an integer number (5020238433).

Almost surely, 2^20003120321 is an apocalyptic number.

It is an amenable number.

20003120321 is a deficient number, since it is larger than the sum of its proper divisors (77833411).

20003120321 is an equidigital number, since it uses as much as digits as its factorization.

20003120321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77833410.

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 20003120321 its reverse (12302130002), we get a palindrome (32305250323).

The spelling of 20003120321 in words is "twenty billion, three million, one hundred twenty thousand, three hundred twenty-one".