1585721147 has 2 divisors, whose sum is σ = 1585721148. Its totient is φ = 1585721146.

The previous prime is 1585721143. The next prime is 1585721161. The reversal of 1585721147 is 7411275851.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1585721147 - 2² = 1585721143 is a prime.

It is not a weakly prime, because it can be changed into another prime (1585721141) 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, 792860573 + 792860574.

It is an arithmetic number, because the mean of its divisors is an integer number (792860574).

Almost surely, 2^1585721147 is an apocalyptic number.

1585721147 is a deficient number, since it is larger than the sum of its proper divisors (1).

1585721147 is an equidigital number, since it uses as much as digits as its factorization.

1585721147 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78400, while the sum is 41.

The square root of 1585721147 is about 39821.1143364924. The cubic root of 1585721147 is about 1166.1173919507.

Adding to 1585721147 its reverse (7411275851), we get a palindrome (8996996998).

The spelling of 1585721147 in words is "one billion, five hundred eighty-five million, seven hundred twenty-one thousand, one hundred forty-seven".