195509137 has 2 divisors, whose sum is σ = 195509138. Its totient is φ = 195509136.

The previous prime is 195509113. The next prime is 195509159. The reversal of 195509137 is 731905591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 164249856 + 31259281 = 12816^2 + 5591^2 .

It is an emirp because it is prime and its reverse (731905591) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195509137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 195509137.

It is not a weakly prime, because it can be changed into another prime (195509837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97754568 + 97754569.

It is an arithmetic number, because the mean of its divisors is an integer number (97754569).

Almost surely, 2^195509137 is an apocalyptic number.

It is an amenable number.

195509137 is a deficient number, since it is larger than the sum of its proper divisors (1).

195509137 is an equidigital number, since it uses as much as digits as its factorization.

195509137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42525, while the sum is 40.

The square root of 195509137 is about 13982.4581887449. The cubic root of 195509137 is about 580.3932499564.

The spelling of 195509137 in words is "one hundred ninety-five million, five hundred nine thousand, one hundred thirty-seven".