1791138197 has 2 divisors, whose sum is σ = 1791138198. Its totient is φ = 1791138196.

The previous prime is 1791138169. The next prime is 1791138247. The reversal of 1791138197 is 7918311971.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 993132196 + 798006001 = 31514^2 + 28249^2 .

It is a cyclic number.

It is not a de Polignac number, because 1791138197 - 2⁸ = 1791137941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1791138157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 895569098 + 895569099.

It is an arithmetic number, because the mean of its divisors is an integer number (895569099).

Almost surely, 2^1791138197 is an apocalyptic number.

It is an amenable number.

1791138197 is a deficient number, since it is larger than the sum of its proper divisors (1).

1791138197 is an equidigital number, since it uses as much as digits as its factorization.

1791138197 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 95256, while the sum is 47.

The square root of 1791138197 is about 42321.8406617671. The cubic root of 1791138197 is about 1214.4408446202.

The spelling of 1791138197 in words is "one billion, seven hundred ninety-one million, one hundred thirty-eight thousand, one hundred ninety-seven".