1309723 has 2 divisors, whose sum is σ = 1309724. Its totient is φ = 1309722.

The previous prime is 1309717. The next prime is 1309739. The reversal of 1309723 is 3279031.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1309723 - 2⁵ = 1309691 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1309753) 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, 654861 + 654862.

It is an arithmetic number, because the mean of its divisors is an integer number (654862).

2^1309723 is an apocalyptic number.

1309723 is a deficient number, since it is larger than the sum of its proper divisors (1).

1309723 is an equidigital number, since it uses as much as digits as its factorization.

1309723 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1134, while the sum is 25.

The square root of 1309723 is about 1144.4312998166. The cubic root of 1309723 is about 109.4107054039.

The spelling of 1309723 in words is "one million, three hundred nine thousand, seven hundred twenty-three".