1390729 has 2 divisors, whose sum is σ = 1390730. Its totient is φ = 1390728.

The previous prime is 1390709. The next prime is 1390733. The reversal of 1390729 is 9270931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1261129 + 129600 = 1123^2 + 360^2 .

It is an emirp because it is prime and its reverse (9270931) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1390729 - 2⁷ = 1390601 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1390729.

It is not a weakly prime, because it can be changed into another prime (1390709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695364 + 695365.

It is an arithmetic number, because the mean of its divisors is an integer number (695365).

2^1390729 is an apocalyptic number.

It is an amenable number.

1390729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1390729 is an equidigital number, since it uses as much as digits as its factorization.

1390729 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3402, while the sum is 31.

The square root of 1390729 is about 1179.2917365945. The cubic root of 1390729 is about 111.6214098430.

The spelling of 1390729 in words is "one million, three hundred ninety thousand, seven hundred twenty-nine".