197247989 has 2 divisors, whose sum is σ = 197247990. Its totient is φ = 197247988.

The previous prime is 197247959. The next prime is 197247997. The reversal of 197247989 is 989742791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197177764 + 70225 = 14042^2 + 265^2 .

It is an emirp because it is prime and its reverse (989742791) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-197247989 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197247959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98623994 + 98623995.

It is an arithmetic number, because the mean of its divisors is an integer number (98623995).

Almost surely, 2^197247989 is an apocalyptic number.

It is an amenable number.

197247989 is a deficient number, since it is larger than the sum of its proper divisors (1).

197247989 is an equidigital number, since it uses as much as digits as its factorization.

197247989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 56.

The square root of 197247989 is about 14044.5003115098. The cubic root of 197247989 is about 582.1088401523.

The spelling of 197247989 in words is "one hundred ninety-seven million, two hundred forty-seven thousand, nine hundred eighty-nine".