291489689 has 2 divisors, whose sum is σ = 291489690. Its totient is φ = 291489688.

The previous prime is 291489661. The next prime is 291489727. The reversal of 291489689 is 986984192.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 211208089 + 80281600 = 14533^2 + 8960^2 .

It is a cyclic number.

It is not a de Polignac number, because 291489689 - 2²⁸ = 23054233 is a prime.

It is not a weakly prime, because it can be changed into another prime (291489619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145744844 + 145744845.

It is an arithmetic number, because the mean of its divisors is an integer number (145744845).

Almost surely, 2^291489689 is an apocalyptic number.

It is an amenable number.

291489689 is a deficient number, since it is larger than the sum of its proper divisors (1).

291489689 is an equidigital number, since it uses as much as digits as its factorization.

291489689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2239488, while the sum is 56.

The square root of 291489689 is about 17073.0691148370. The cubic root of 291489689 is about 663.0420400321.

The spelling of 291489689 in words is "two hundred ninety-one million, four hundred eighty-nine thousand, six hundred eighty-nine".