291081589 has 2 divisors, whose sum is σ = 291081590. Its totient is φ = 291081588.

The previous prime is 291081551. The next prime is 291081601. The reversal of 291081589 is 985180192.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 192238225 + 98843364 = 13865^2 + 9942^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-291081589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (291081529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145540794 + 145540795.

It is an arithmetic number, because the mean of its divisors is an integer number (145540795).

Almost surely, 2^291081589 is an apocalyptic number.

It is an amenable number.

291081589 is a deficient number, since it is larger than the sum of its proper divisors (1).

291081589 is an equidigital number, since it uses as much as digits as its factorization.

291081589 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 43.

The square root of 291081589 is about 17061.1133575743. The cubic root of 291081589 is about 662.7324649497.

The spelling of 291081589 in words is "two hundred ninety-one million, eighty-one thousand, five hundred eighty-nine".