20510530321 has 2 divisors, whose sum is σ = 20510530322. Its totient is φ = 20510530320.

The previous prime is 20510530319. The next prime is 20510530357. The reversal of 20510530321 is 12303501502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14941639696 + 5568890625 = 122236^2 + 74625^2 .

It is a cyclic number.

It is not a de Polignac number, because 20510530321 - 2¹ = 20510530319 is a prime.

Together with 20510530319, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20510530292 and 20510530301.

It is not a weakly prime, because it can be changed into another prime (20510534321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10255265160 + 10255265161.

It is an arithmetic number, because the mean of its divisors is an integer number (10255265161).

Almost surely, 2^20510530321 is an apocalyptic number.

It is an amenable number.

20510530321 is a deficient number, since it is larger than the sum of its proper divisors (1).

20510530321 is an equidigital number, since it uses as much as digits as its factorization.

20510530321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 900, while the sum is 22.

The spelling of 20510530321 in words is "twenty billion, five hundred ten million, five hundred thirty thousand, three hundred twenty-one".