21917683 has 2 divisors, whose sum is σ = 21917684. Its totient is φ = 21917682.

The previous prime is 21917677. The next prime is 21917699. The reversal of 21917683 is 38671912.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21917683 - 2⁹ = 21917171 is a prime.

It is not a weakly prime, because it can be changed into another prime (21917633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10958841 + 10958842.

It is an arithmetic number, because the mean of its divisors is an integer number (10958842).

Almost surely, 2^21917683 is an apocalyptic number.

21917683 is a deficient number, since it is larger than the sum of its proper divisors (1).

21917683 is an equidigital number, since it uses as much as digits as its factorization.

21917683 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 21917683 is about 4681.6325144120. The cubic root of 21917683 is about 279.8540182915.

The spelling of 21917683 in words is "twenty-one million, nine hundred seventeen thousand, six hundred eighty-three".