195720397 has 2 divisors, whose sum is σ = 195720398. Its totient is φ = 195720396.

The previous prime is 195720379. The next prime is 195720431. The reversal of 195720397 is 793027591.

Together with previous prime (195720379) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123232201 + 72488196 = 11101^2 + 8514^2 .

It is a cyclic number.

It is not a de Polignac number, because 195720397 - 2¹¹ = 195718349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195720377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97860198 + 97860199.

It is an arithmetic number, because the mean of its divisors is an integer number (97860199).

Almost surely, 2^195720397 is an apocalyptic number.

It is an amenable number.

195720397 is a deficient number, since it is larger than the sum of its proper divisors (1).

195720397 is an equidigital number, since it uses as much as digits as its factorization.

195720397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 119070, while the sum is 43.

The square root of 195720397 is about 13990.0106147208. The cubic root of 195720397 is about 580.6022252543.

The spelling of 195720397 in words is "one hundred ninety-five million, seven hundred twenty thousand, three hundred ninety-seven".