20001320321 has 8 divisors (see below), whose sum is σ = 20508369000. Its totient is φ = 19495186560.

The previous prime is 20001320309. The next prime is 20001320333. The reversal of 20001320321 is 12302310002.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20001320309) and next prime (20001320333).

It can be written as a sum of positive squares in 4 ways, for example, as 1022400625 + 18978919696 = 31975^2 + 137764^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20001320321 - 2¹⁴ = 20001303937 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20001320296 and 20001320305.

It is not an unprimeable number, because it can be changed into a prime (20001320371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 184346 + ... + 272003.

It is an arithmetic number, because the mean of its divisors is an integer number (2563546125).

Almost surely, 2^20001320321 is an apocalyptic number.

It is an amenable number.

20001320321 is a deficient number, since it is larger than the sum of its proper divisors (507048679).

20001320321 is a wasteful number, since it uses less digits than its factorization.

20001320321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457459.

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

Adding to 20001320321 its reverse (12302310002), we get a palindrome (32303630323).

The spelling of 20001320321 in words is "twenty billion, one million, three hundred twenty thousand, three hundred twenty-one".