195012109 has 2 divisors, whose sum is σ = 195012110. Its totient is φ = 195012108.

The previous prime is 195012091. The next prime is 195012137. The reversal of 195012109 is 901210591.

Together with previous prime (195012091) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (195012137) can be obtained adding 195012109 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171217225 + 23794884 = 13085^2 + 4878^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195012109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195012149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97506054 + 97506055.

It is an arithmetic number, because the mean of its divisors is an integer number (97506055).

Almost surely, 2^195012109 is an apocalyptic number.

It is an amenable number.

195012109 is a deficient number, since it is larger than the sum of its proper divisors (1).

195012109 is an equidigital number, since it uses as much as digits as its factorization.

195012109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 810, while the sum is 28.

The square root of 195012109 is about 13964.6736087887. The cubic root of 195012109 is about 579.9010027231.

The spelling of 195012109 in words is "one hundred ninety-five million, twelve thousand, one hundred nine".