194630021 has 2 divisors, whose sum is σ = 194630022. Its totient is φ = 194630020.

The previous prime is 194629951. The next prime is 194630047. The reversal of 194630021 is 120036491.

194630021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an a-pointer prime, because the next prime (194630047) can be obtained adding 194630021 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 192820996 + 1809025 = 13886^2 + 1345^2 .

It is an emirp because it is prime and its reverse (120036491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 194630021 - 2¹⁰ = 194628997 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194630081) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97315010 + 97315011.

It is an arithmetic number, because the mean of its divisors is an integer number (97315011).

Almost surely, 2^194630021 is an apocalyptic number.

It is an amenable number.

194630021 is a deficient number, since it is larger than the sum of its proper divisors (1).

194630021 is an equidigital number, since it uses as much as digits as its factorization.

194630021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 194630021 is about 13950.9863808979. The cubic root of 194630021 is about 579.5220209889.

The spelling of 194630021 in words is "one hundred ninety-four million, six hundred thirty thousand, twenty-one".