291328057 has 2 divisors, whose sum is σ = 291328058. Its totient is φ = 291328056.

The previous prime is 291328033. The next prime is 291328067. The reversal of 291328057 is 750823192.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 176066361 + 115261696 = 13269^2 + 10736^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-291328057 is a prime.

It is not a weakly prime, because it can be changed into another prime (291328067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145664028 + 145664029.

It is an arithmetic number, because the mean of its divisors is an integer number (145664029).

Almost surely, 2^291328057 is an apocalyptic number.

It is an amenable number.

291328057 is a deficient number, since it is larger than the sum of its proper divisors (1).

291328057 is an equidigital number, since it uses as much as digits as its factorization.

291328057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 291328057 is about 17068.3349217198. The cubic root of 291328057 is about 662.9194643692.

The spelling of 291328057 in words is "two hundred ninety-one million, three hundred twenty-eight thousand, fifty-seven".