21703508873 has 2 divisors, whose sum is σ = 21703508874. Its totient is φ = 21703508872.

The previous prime is 21703508861. The next prime is 21703508903. The reversal of 21703508873 is 37880530712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20413837129 + 1289671744 = 142877^2 + 35912^2 .

It is a cyclic number.

It is not a de Polignac number, because 21703508873 - 2¹⁰ = 21703507849 is a prime.

It is not a weakly prime, because it can be changed into another prime (21703558873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10851754436 + 10851754437.

It is an arithmetic number, because the mean of its divisors is an integer number (10851754437).

Almost surely, 2^21703508873 is an apocalyptic number.

It is an amenable number.

21703508873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21703508873 is an equidigital number, since it uses as much as digits as its factorization.

21703508873 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 282240, while the sum is 44.

The spelling of 21703508873 in words is "twenty-one billion, seven hundred three million, five hundred eight thousand, eight hundred seventy-three".