21035355317 has 2 divisors, whose sum is σ = 21035355318. Its totient is φ = 21035355316.

The previous prime is 21035355293. The next prime is 21035355337. The reversal of 21035355317 is 71355353012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15553581796 + 5481773521 = 124714^2 + 74039^2 .

It is a cyclic number.

It is not a de Polignac number, because 21035355317 - 2¹² = 21035351221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21035355337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10517677658 + 10517677659.

It is an arithmetic number, because the mean of its divisors is an integer number (10517677659).

Almost surely, 2^21035355317 is an apocalyptic number.

It is an amenable number.

21035355317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21035355317 is an equidigital number, since it uses as much as digits as its factorization.

21035355317 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 47250, while the sum is 35.

The spelling of 21035355317 in words is "twenty-one billion, thirty-five million, three hundred fifty-five thousand, three hundred seventeen".