197709961 has 2 divisors, whose sum is σ = 197709962. Its totient is φ = 197709960.

The previous prime is 197709899. The next prime is 197709989. The reversal of 197709961 is 169907791.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 164865600 + 32844361 = 12840^2 + 5731^2 .

It is a cyclic number.

It is not a de Polignac number, because 197709961 - 2¹³ = 197701769 is a prime.

It is not a weakly prime, because it can be changed into another prime (197709361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98854980 + 98854981.

It is an arithmetic number, because the mean of its divisors is an integer number (98854981).

Almost surely, 2^197709961 is an apocalyptic number.

It is an amenable number.

197709961 is a deficient number, since it is larger than the sum of its proper divisors (1).

197709961 is an equidigital number, since it uses as much as digits as its factorization.

197709961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 214326, while the sum is 49.

The square root of 197709961 is about 14060.9374154073. The cubic root of 197709961 is about 582.5629357236.

The spelling of 197709961 in words is "one hundred ninety-seven million, seven hundred nine thousand, nine hundred sixty-one".