209819429 has 2 divisors, whose sum is σ = 209819430. Its totient is φ = 209819428.

The previous prime is 209819387. The next prime is 209819503. The reversal of 209819429 is 924918902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 203718529 + 6100900 = 14273^2 + 2470^2 .

It is a cyclic number.

It is not a de Polignac number, because 209819429 - 2⁸ = 209819173 is a prime.

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 209819429.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (209819329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104909714 + 104909715.

It is an arithmetic number, because the mean of its divisors is an integer number (104909715).

Almost surely, 2^209819429 is an apocalyptic number.

It is an amenable number.

209819429 is a deficient number, since it is larger than the sum of its proper divisors (1).

209819429 is an equidigital number, since it uses as much as digits as its factorization.

209819429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 209819429 is about 14485.1451149100. The cubic root of 209819429 is about 594.2217813544.

The spelling of 209819429 in words is "two hundred nine million, eight hundred nineteen thousand, four hundred twenty-nine".