195977491 has 2 divisors, whose sum is σ = 195977492. Its totient is φ = 195977490.

The previous prime is 195977477. The next prime is 195977497. The reversal of 195977491 is 194779591.

195977491 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 195977491 - 2²³ = 187588883 is a prime.

It is not a weakly prime, because it can be changed into another prime (195977497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97988745 + 97988746.

It is an arithmetic number, because the mean of its divisors is an integer number (97988746).

Almost surely, 2^195977491 is an apocalyptic number.

195977491 is a deficient number, since it is larger than the sum of its proper divisors (1).

195977491 is an equidigital number, since it uses as much as digits as its factorization.

195977491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 714420, while the sum is 52.

The square root of 195977491 is about 13999.1960840614. The cubic root of 195977491 is about 580.8563361177.

The spelling of 195977491 in words is "one hundred ninety-five million, nine hundred seventy-seven thousand, four hundred ninety-one".