68990191 has 2 divisors, whose sum is σ = 68990192. Its totient is φ = 68990190.

The previous prime is 68990177. The next prime is 68990227. The reversal of 68990191 is 19109986.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-68990191 is a prime.

It is a super-3 number, since 3×68990191³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (68990491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34495095 + 34495096.

It is an arithmetic number, because the mean of its divisors is an integer number (34495096).

Almost surely, 2^68990191 is an apocalyptic number.

68990191 is a deficient number, since it is larger than the sum of its proper divisors (1).

68990191 is an equidigital number, since it uses as much as digits as its factorization.

68990191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 34992, while the sum is 43.

The square root of 68990191 is about 8306.0334095162. The cubic root of 68990191 is about 410.1371561747.

The spelling of 68990191 in words is "sixty-eight million, nine hundred ninety thousand, one hundred ninety-one".