20321310173 has 2 divisors, whose sum is σ = 20321310174. Its totient is φ = 20321310172.

The previous prime is 20321310169. The next prime is 20321310319. The reversal of 20321310173 is 37101312302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19360496164 + 960814009 = 139142^2 + 30997^2 .

It is a cyclic number.

It is not a de Polignac number, because 20321310173 - 2² = 20321310169 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20321310973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10160655086 + 10160655087.

It is an arithmetic number, because the mean of its divisors is an integer number (10160655087).

Almost surely, 2^20321310173 is an apocalyptic number.

It is an amenable number.

20321310173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20321310173 is an equidigital number, since it uses as much as digits as its factorization.

20321310173 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 23.

Adding to 20321310173 its reverse (37101312302), we get a palindrome (57422622475).

The spelling of 20321310173 in words is "twenty billion, three hundred twenty-one million, three hundred ten thousand, one hundred seventy-three".