1720220223 has 4 divisors (see below), whose sum is σ = 2293626968. Its totient is φ = 1146813480.

The previous prime is 1720220221. The next prime is 1720220321. The reversal of 1720220223 is 3220220271.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1720220223 - 2¹ = 1720220221 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1720220223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720220221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 286703368 + ... + 286703373.

It is an arithmetic number, because the mean of its divisors is an integer number (573406742).

Almost surely, 2^1720220223 is an apocalyptic number.

1720220223 is a deficient number, since it is larger than the sum of its proper divisors (573406745).

1720220223 is an equidigital number, since it uses as much as digits as its factorization.

1720220223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 573406744.

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 1720220223 is about 41475.5376457015. The cubic root of 1720220223 is about 1198.1964162907.

Adding to 1720220223 its reverse (3220220271), we get a palindrome (4940440494).

The spelling of 1720220223 in words is "one billion, seven hundred twenty million, two hundred twenty thousand, two hundred twenty-three".