197980009 has 2 divisors, whose sum is σ = 197980010. Its totient is φ = 197980008.

The previous prime is 197980001. The next prime is 197980031. The reversal of 197980009 is 900089791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 188980009 + 9000000 = 13747^2 + 3000^2 .

It is a cyclic number.

It is not a de Polignac number, because 197980009 - 2³ = 197980001 is a prime.

It is not a weakly prime, because it can be changed into another prime (197980001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98990004 + 98990005.

It is an arithmetic number, because the mean of its divisors is an integer number (98990005).

Almost surely, 2^197980009 is an apocalyptic number.

It is an amenable number.

197980009 is a deficient number, since it is larger than the sum of its proper divisors (1).

197980009 is an equidigital number, since it uses as much as digits as its factorization.

197980009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 43.

The square root of 197980009 is about 14070.5369122859. The cubic root of 197980009 is about 582.8280519954.

The spelling of 197980009 in words is "one hundred ninety-seven million, nine hundred eighty thousand, nine".