195420809 has 2 divisors, whose sum is σ = 195420810. Its totient is φ = 195420808.

The previous prime is 195420787. The next prime is 195420851. The reversal of 195420809 is 908024591.

195420809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 186923584 + 8497225 = 13672^2 + 2915^2 .

It is a cyclic number.

It is not a de Polignac number, because 195420809 - 2¹² = 195416713 is a prime.

It is not a weakly prime, because it can be changed into another prime (195420859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97710404 + 97710405.

It is an arithmetic number, because the mean of its divisors is an integer number (97710405).

Almost surely, 2^195420809 is an apocalyptic number.

It is an amenable number.

195420809 is a deficient number, since it is larger than the sum of its proper divisors (1).

195420809 is an equidigital number, since it uses as much as digits as its factorization.

195420809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 195420809 is about 13979.2993028978. The cubic root of 195420809 is about 580.3058325634.

The spelling of 195420809 in words is "one hundred ninety-five million, four hundred twenty thousand, eight hundred nine".