21412717 has 2 divisors, whose sum is σ = 21412718. Its totient is φ = 21412716.

The previous prime is 21412697. The next prime is 21412739. The reversal of 21412717 is 71721412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19483396 + 1929321 = 4414^2 + 1389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21412717 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21412691 and 21412700.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21412217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10706358 + 10706359.

It is an arithmetic number, because the mean of its divisors is an integer number (10706359).

Almost surely, 2^21412717 is an apocalyptic number.

It is an amenable number.

21412717 is a deficient number, since it is larger than the sum of its proper divisors (1).

21412717 is an equidigital number, since it uses as much as digits as its factorization.

21412717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 784, while the sum is 25.

The square root of 21412717 is about 4627.3877079838. The cubic root of 21412717 is about 277.6880936726.

The spelling of 21412717 in words is "twenty-one million, four hundred twelve thousand, seven hundred seventeen".