291350561 has 2 divisors, whose sum is σ = 291350562. Its totient is φ = 291350560.

The previous prime is 291350557. The next prime is 291350581. The reversal of 291350561 is 165053192.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 146870161 + 144480400 = 12119^2 + 12020^2 .

It is a cyclic number.

It is not a de Polignac number, because 291350561 - 2² = 291350557 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (291350531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145675280 + 145675281.

It is an arithmetic number, because the mean of its divisors is an integer number (145675281).

Almost surely, 2^291350561 is an apocalyptic number.

It is an amenable number.

291350561 is a deficient number, since it is larger than the sum of its proper divisors (1).

291350561 is an equidigital number, since it uses as much as digits as its factorization.

291350561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8100, while the sum is 32.

The square root of 291350561 is about 17068.9941414250. The cubic root of 291350561 is about 662.9365332773.

The spelling of 291350561 in words is "two hundred ninety-one million, three hundred fifty thousand, five hundred sixty-one".