21010010617 has 2 divisors, whose sum is σ = 21010010618. Its totient is φ = 21010010616.

The previous prime is 21010010599. The next prime is 21010010621. The reversal of 21010010617 is 71601001012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15656015376 + 5353995241 = 125124^2 + 73171^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21010010617 is a prime.

It is a super-2 number, since 2×21010010617² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21010010594 and 21010010603.

It is not a weakly prime, because it can be changed into another prime (21010010647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505005308 + 10505005309.

It is an arithmetic number, because the mean of its divisors is an integer number (10505005309).

Almost surely, 2^21010010617 is an apocalyptic number.

It is an amenable number.

21010010617 is a deficient number, since it is larger than the sum of its proper divisors (1).

21010010617 is an equidigital number, since it uses as much as digits as its factorization.

21010010617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 84, while the sum is 19.

Adding to 21010010617 its reverse (71601001012), we get a palindrome (92611011629).

The spelling of 21010010617 in words is "twenty-one billion, ten million, ten thousand, six hundred seventeen".