191665351 has 2 divisors, whose sum is σ = 191665352. Its totient is φ = 191665350.

The previous prime is 191665337. The next prime is 191665363. The reversal of 191665351 is 153566191.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 191665351 - 2⁹ = 191664839 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 191665351.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (191665051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95832675 + 95832676.

It is an arithmetic number, because the mean of its divisors is an integer number (95832676).

Almost surely, 2^191665351 is an apocalyptic number.

191665351 is a deficient number, since it is larger than the sum of its proper divisors (1).

191665351 is an equidigital number, since it uses as much as digits as its factorization.

191665351 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24300, while the sum is 37.

The square root of 191665351 is about 13844.3255884857. The cubic root of 191665351 is about 576.5644614142.

The spelling of 191665351 in words is "one hundred ninety-one million, six hundred sixty-five thousand, three hundred fifty-one".