21682937 has 2 divisors, whose sum is σ = 21682938. Its totient is φ = 21682936.

The previous prime is 21682931. The next prime is 21682963. The reversal of 21682937 is 73928612.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13278736 + 8404201 = 3644^2 + 2899^2 .

It is a cyclic number.

It is not a de Polignac number, because 21682937 - 2⁸ = 21682681 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21682937.

It is not a weakly prime, because it can be changed into another prime (21682931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10841468 + 10841469.

It is an arithmetic number, because the mean of its divisors is an integer number (10841469).

Almost surely, 2^21682937 is an apocalyptic number.

It is an amenable number.

21682937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21682937 is an equidigital number, since it uses as much as digits as its factorization.

21682937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 38.

The square root of 21682937 is about 4656.4940674288. The cubic root of 21682937 is about 278.8513187158.

The spelling of 21682937 in words is "twenty-one million, six hundred eighty-two thousand, nine hundred thirty-seven".