194426021 has 2 divisors, whose sum is σ = 194426022. Its totient is φ = 194426020.

The previous prime is 194425997. The next prime is 194426033. The reversal of 194426021 is 120624491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155500900 + 38925121 = 12470^2 + 6239^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-194426021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194426321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97213010 + 97213011.

It is an arithmetic number, because the mean of its divisors is an integer number (97213011).

Almost surely, 2^194426021 is an apocalyptic number.

It is an amenable number.

194426021 is a deficient number, since it is larger than the sum of its proper divisors (1).

194426021 is an equidigital number, since it uses as much as digits as its factorization.

194426021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 194426021 is about 13943.6731530827. The cubic root of 194426021 is about 579.3194763173.

The spelling of 194426021 in words is "one hundred ninety-four million, four hundred twenty-six thousand, twenty-one".