1628729 has 2 divisors, whose sum is σ = 1628730. Its totient is φ = 1628728.

The previous prime is 1628701. The next prime is 1628747. The reversal of 1628729 is 9278261.

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., 1428025 + 200704 = 1195^2 + 448^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1628729 is a prime.

It is a Chen prime.

It is a plaindrome in base 15.

It is not a weakly prime, because it can be changed into another prime (1628779) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 814364 + 814365.

It is an arithmetic number, because the mean of its divisors is an integer number (814365).

2^1628729 is an apocalyptic number.

It is an amenable number.

1628729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1628729 is an equidigital number, since it uses as much as digits as its factorization.

1628729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 35.

The square root of 1628729 is about 1276.2166743935. The cubic root of 1628729 is about 117.6565951927.

The spelling of 1628729 in words is "one million, six hundred twenty-eight thousand, seven hundred twenty-nine".