195191797 has 2 divisors, whose sum is σ = 195191798. Its totient is φ = 195191796.

The previous prime is 195191791. The next prime is 195191809. The reversal of 195191797 is 797191591.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 114083761 + 81108036 = 10681^2 + 9006^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195191797 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 195191797.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195191791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97595898 + 97595899.

It is an arithmetic number, because the mean of its divisors is an integer number (97595899).

Almost surely, 2^195191797 is an apocalyptic number.

It is an amenable number.

195191797 is a deficient number, since it is larger than the sum of its proper divisors (1).

195191797 is an equidigital number, since it uses as much as digits as its factorization.

195191797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 178605, while the sum is 49.

The square root of 195191797 is about 13971.1057901656. The cubic root of 195191797 is about 580.0790587832.

It can be divided in two parts, 19519 and 1797, that added together give a square (21316 = 146²).

The spelling of 195191797 in words is "one hundred ninety-five million, one hundred ninety-one thousand, seven hundred ninety-seven".