21003103313 has 2 divisors, whose sum is σ = 21003103314. Its totient is φ = 21003103312.

The previous prime is 21003103301. The next prime is 21003103321. The reversal of 21003103313 is 31330130012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15265343809 + 5737759504 = 123553^2 + 75748^2 .

It is a cyclic number.

It is not a de Polignac number, because 21003103313 - 2²⁶ = 20935994449 is a prime.

It is a super-2 number, since 2×21003103313² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21003103291 and 21003103300.

It is not a weakly prime, because it can be changed into another prime (21003103393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501551656 + 10501551657.

It is an arithmetic number, because the mean of its divisors is an integer number (10501551657).

Almost surely, 2^21003103313 is an apocalyptic number.

It is an amenable number.

21003103313 is a deficient number, since it is larger than the sum of its proper divisors (1).

21003103313 is an equidigital number, since it uses as much as digits as its factorization.

21003103313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 17.

Adding to 21003103313 its reverse (31330130012), we get a palindrome (52333233325).

The spelling of 21003103313 in words is "twenty-one billion, three million, one hundred three thousand, three hundred thirteen".