195978151 has 2 divisors, whose sum is σ = 195978152. Its totient is φ = 195978150.

The previous prime is 195978137. The next prime is 195978157. The reversal of 195978151 is 151879591.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 195978151 - 2⁵ = 195978119 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195978157) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97989075 + 97989076.

It is an arithmetic number, because the mean of its divisors is an integer number (97989076).

Almost surely, 2^195978151 is an apocalyptic number.

195978151 is a deficient number, since it is larger than the sum of its proper divisors (1).

195978151 is an equidigital number, since it uses as much as digits as its factorization.

195978151 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 113400, while the sum is 46.

The square root of 195978151 is about 13999.2196568237. The cubic root of 195978151 is about 580.8569881734.

The spelling of 195978151 in words is "one hundred ninety-five million, nine hundred seventy-eight thousand, one hundred fifty-one".