1721299 has 2 divisors, whose sum is σ = 1721300. Its totient is φ = 1721298.

The previous prime is 1721273. The next prime is 1721323. The reversal of 1721299 is 9921271.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1721299 - 2⁹ = 1720787 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1721299.

It is not a weakly prime, because it can be changed into another prime (1721899) 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, 860649 + 860650.

It is an arithmetic number, because the mean of its divisors is an integer number (860650).

2^1721299 is an apocalyptic number.

1721299 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721299 is an equidigital number, since it uses as much as digits as its factorization.

1721299 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2268, while the sum is 31.

The square root of 1721299 is about 1311.9828504977. The cubic root of 1721299 is about 119.8446833187.

It can be divided in two parts, 17 and 21299, that added together give a square (21316 = 146²).

The spelling of 1721299 in words is "one million, seven hundred twenty-one thousand, two hundred ninety-nine".