20659943 has 2 divisors, whose sum is σ = 20659944. Its totient is φ = 20659942.

The previous prime is 20659927. The next prime is 20659997. The reversal of 20659943 is 34995602.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20659943 - 2⁴ = 20659927 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20659897 and 20659906.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20659343) 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, 10329971 + 10329972.

It is an arithmetic number, because the mean of its divisors is an integer number (10329972).

Almost surely, 2^20659943 is an apocalyptic number.

20659943 is a deficient number, since it is larger than the sum of its proper divisors (1).

20659943 is an equidigital number, since it uses as much as digits as its factorization.

20659943 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 20659943 is about 4545.3210007655. The cubic root of 20659943 is about 274.3951134499.

The spelling of 20659943 in words is "twenty million, six hundred fifty-nine thousand, nine hundred forty-three".