1721238413 has 2 divisors, whose sum is σ = 1721238414. Its totient is φ = 1721238412.

The previous prime is 1721238397. The next prime is 1721238427. The reversal of 1721238413 is 3148321271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1505207209 + 216031204 = 38797^2 + 14698^2 .

It is an emirp because it is prime and its reverse (3148321271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1721238413 - 2⁴ = 1721238397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1721238413.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1721238473) 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, 860619206 + 860619207.

It is an arithmetic number, because the mean of its divisors is an integer number (860619207).

Almost surely, 2^1721238413 is an apocalyptic number.

It is an amenable number.

1721238413 is a deficient number, since it is larger than the sum of its proper divisors (1).

1721238413 is an equidigital number, since it uses as much as digits as its factorization.

1721238413 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8064, while the sum is 32.

The square root of 1721238413 is about 41487.8104146266. The cubic root of 1721238413 is about 1198.4327718785.

Adding to 1721238413 its reverse (3148321271), we get a palindrome (4869559684).

The spelling of 1721238413 in words is "one billion, seven hundred twenty-one million, two hundred thirty-eight thousand, four hundred thirteen".