20194661 has 2 divisors, whose sum is σ = 20194662. Its totient is φ = 20194660.

The previous prime is 20194639. The next prime is 20194703. The reversal of 20194661 is 16649102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12180100 + 8014561 = 3490^2 + 2831^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20194661 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20194061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10097330 + 10097331.

It is an arithmetic number, because the mean of its divisors is an integer number (10097331).

Almost surely, 2^20194661 is an apocalyptic number.

It is an amenable number.

20194661 is a deficient number, since it is larger than the sum of its proper divisors (1).

20194661 is an equidigital number, since it uses as much as digits as its factorization.

20194661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 20194661 is about 4493.8470156426. The cubic root of 20194661 is about 272.3195719451.

The spelling of 20194661 in words is "twenty million, one hundred ninety-four thousand, six hundred sixty-one".