21693713 has 2 divisors, whose sum is σ = 21693714. Its totient is φ = 21693712.

The previous prime is 21693703. The next prime is 21693739. The reversal of 21693713 is 31739612.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13786369 + 7907344 = 3713^2 + 2812^2 .

It is a cyclic number.

It is not a de Polignac number, because 21693713 - 2⁴ = 21693697 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21693713.

It is not a weakly prime, because it can be changed into another prime (21693703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10846856 + 10846857.

It is an arithmetic number, because the mean of its divisors is an integer number (10846857).

Almost surely, 2^21693713 is an apocalyptic number.

It is an amenable number.

21693713 is a deficient number, since it is larger than the sum of its proper divisors (1).

21693713 is an equidigital number, since it uses as much as digits as its factorization.

21693713 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6804, while the sum is 32.

The square root of 21693713 is about 4657.6510174121. The cubic root of 21693713 is about 278.8975056346.

The spelling of 21693713 in words is "twenty-one million, six hundred ninety-three thousand, seven hundred thirteen".