21084673 has 2 divisors, whose sum is σ = 21084674. Its totient is φ = 21084672.

The previous prime is 21084649. The next prime is 21084677. The reversal of 21084673 is 37648012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19158129 + 1926544 = 4377^2 + 1388^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21084673 is a prime.

It is not a weakly prime, because it can be changed into another prime (21084677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10542336 + 10542337.

It is an arithmetic number, because the mean of its divisors is an integer number (10542337).

Almost surely, 2^21084673 is an apocalyptic number.

It is an amenable number.

21084673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21084673 is an equidigital number, since it uses as much as digits as its factorization.

21084673 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21084673 is about 4591.8049827927. The cubic root of 21084673 is about 276.2627241738.

The spelling of 21084673 in words is "twenty-one million, eighty-four thousand, six hundred seventy-three".