21031303273 has 2 divisors, whose sum is σ = 21031303274. Its totient is φ = 21031303272.

The previous prime is 21031303229. The next prime is 21031303343. The reversal of 21031303273 is 37230313012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18623242089 + 2408061184 = 136467^2 + 49072^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21031303273 is a prime.

It is not a weakly prime, because it can be changed into another prime (21031303673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10515651636 + 10515651637.

It is an arithmetic number, because the mean of its divisors is an integer number (10515651637).

Almost surely, 2^21031303273 is an apocalyptic number.

It is an amenable number.

21031303273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031303273 is an equidigital number, since it uses as much as digits as its factorization.

21031303273 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2268, while the sum is 25.

Adding to 21031303273 its reverse (37230313012), we get a palindrome (58261616285).

The spelling of 21031303273 in words is "twenty-one billion, thirty-one million, three hundred three thousand, two hundred seventy-three".