197137691 has 2 divisors, whose sum is σ = 197137692. Its totient is φ = 197137690.

The previous prime is 197137643. The next prime is 197137709. The reversal of 197137691 is 196731791.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-197137691 is a prime.

It is a super-2 number, since 2×197137691² = 77726538425622962, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (197187691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98568845 + 98568846.

It is an arithmetic number, because the mean of its divisors is an integer number (98568846).

Almost surely, 2^197137691 is an apocalyptic number.

197137691 is a deficient number, since it is larger than the sum of its proper divisors (1).

197137691 is an equidigital number, since it uses as much as digits as its factorization.

197137691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 71442, while the sum is 44.

The square root of 197137691 is about 14040.5730296167. The cubic root of 197137691 is about 582.0003178594. Note that the first 3 decimals are identical.

The spelling of 197137691 in words is "one hundred ninety-seven million, one hundred thirty-seven thousand, six hundred ninety-one".