195191081 has 2 divisors, whose sum is σ = 195191082. Its totient is φ = 195191080.

The previous prime is 195191071. The next prime is 195191089. The reversal of 195191081 is 180191591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 173185600 + 22005481 = 13160^2 + 4691^2 .

It is a cyclic number.

It is not a de Polignac number, because 195191081 - 2²² = 190996777 is a prime.

It is a super-2 number, since 2×195191081² = 76199116203897122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (195191089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97595540 + 97595541.

It is an arithmetic number, because the mean of its divisors is an integer number (97595541).

Almost surely, 2^195191081 is an apocalyptic number.

It is an amenable number.

195191081 is a deficient number, since it is larger than the sum of its proper divisors (1).

195191081 is an equidigital number, since it uses as much as digits as its factorization.

195191081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3240, while the sum is 35.

The square root of 195191081 is about 13971.0801658283. The cubic root of 195191081 is about 580.0783495029.

The spelling of 195191081 in words is "one hundred ninety-five million, one hundred ninety-one thousand, eighty-one".