195929891 has 2 divisors, whose sum is σ = 195929892. Its totient is φ = 195929890.

The previous prime is 195929873. The next prime is 195929897. The reversal of 195929891 is 198929591.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-195929891 is a prime.

It is not a weakly prime, because it can be changed into another prime (195929897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97964945 + 97964946.

It is an arithmetic number, because the mean of its divisors is an integer number (97964946).

Almost surely, 2^195929891 is an apocalyptic number.

195929891 is a deficient number, since it is larger than the sum of its proper divisors (1).

195929891 is an equidigital number, since it uses as much as digits as its factorization.

195929891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 524880, while the sum is 53.

The square root of 195929891 is about 13997.4958831928. The cubic root of 195929891 is about 580.8093052057.

The spelling of 195929891 in words is "one hundred ninety-five million, nine hundred twenty-nine thousand, eight hundred ninety-one".