1399709 has 2 divisors, whose sum is σ = 1399710. Its totient is φ = 1399708.

The previous prime is 1399691. The next prime is 1399721. The reversal of 1399709 is 9079931.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1315609 + 84100 = 1147^2 + 290^2 .

It is a cyclic number.

It is not a de Polignac number, because 1399709 - 2¹² = 1395613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1399789) 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, 699854 + 699855.

It is an arithmetic number, because the mean of its divisors is an integer number (699855).

2^1399709 is an apocalyptic number.

It is an amenable number.

1399709 is a deficient number, since it is larger than the sum of its proper divisors (1).

1399709 is an equidigital number, since it uses as much as digits as its factorization.

1399709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15309, while the sum is 38.

The square root of 1399709 is about 1183.0929802852. The cubic root of 1399709 is about 111.8611427548.

The spelling of 1399709 in words is "one million, three hundred ninety-nine thousand, seven hundred nine".