189790409 has 2 divisors, whose sum is σ = 189790410. Its totient is φ = 189790408.

The previous prime is 189790399. The next prime is 189790421. The reversal of 189790409 is 904097981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 142730809 + 47059600 = 11947^2 + 6860^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-189790409 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (189790429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94895204 + 94895205.

It is an arithmetic number, because the mean of its divisors is an integer number (94895205).

Almost surely, 2^189790409 is an apocalyptic number.

It is an amenable number.

189790409 is a deficient number, since it is larger than the sum of its proper divisors (1).

189790409 is an equidigital number, since it uses as much as digits as its factorization.

189790409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 163296, while the sum is 47.

The square root of 189790409 is about 13776.4439896513. The cubic root of 189790409 is about 574.6782411556.

The spelling of 189790409 in words is "one hundred eighty-nine million, seven hundred ninety thousand, four hundred nine".