197399879 has 2 divisors, whose sum is σ = 197399880. Its totient is φ = 197399878.

The previous prime is 197399863. The next prime is 197399887. The reversal of 197399879 is 978993791.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 197399879 - 2⁴ = 197399863 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197399849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98699939 + 98699940.

It is an arithmetic number, because the mean of its divisors is an integer number (98699940).

Almost surely, 2^197399879 is an apocalyptic number.

197399879 is a deficient number, since it is larger than the sum of its proper divisors (1).

197399879 is an equidigital number, since it uses as much as digits as its factorization.

197399879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7715736, while the sum is 62.

The square root of 197399879 is about 14049.9067256690. The cubic root of 197399879 is about 582.2582186529.

The spelling of 197399879 in words is "one hundred ninety-seven million, three hundred ninety-nine thousand, eight hundred seventy-nine".