20690441 has 2 divisors, whose sum is σ = 20690442. Its totient is φ = 20690440.

The previous prime is 20690429. The next prime is 20690443. The reversal of 20690441 is 14409602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11055625 + 9634816 = 3325^2 + 3104^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20690441 is a prime.

Together with 20690443, it forms a pair of twin primes.

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 20690441.

It is not a weakly prime, because it can be changed into another prime (20690443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10345220 + 10345221.

It is an arithmetic number, because the mean of its divisors is an integer number (10345221).

Almost surely, 2^20690441 is an apocalyptic number.

It is an amenable number.

20690441 is a deficient number, since it is larger than the sum of its proper divisors (1).

20690441 is an equidigital number, since it uses as much as digits as its factorization.

20690441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 20690441 is about 4548.6746421348. The cubic root of 20690441 is about 274.5300668346.

The spelling of 20690441 in words is "twenty million, six hundred ninety thousand, four hundred forty-one".