1720339673 has 4 divisors (see below), whose sum is σ = 1852673508. Its totient is φ = 1588005840.

The previous prime is 1720339669. The next prime is 1720339721. The reversal of 1720339673 is 3769330271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3769330271 = 7 ⋅538475753.

It can be written as a sum of positive squares in 2 ways, for example, as 565155529 + 1155184144 = 23773^2 + 33988^2 .

It is a cyclic number.

It is not a de Polignac number, because 1720339673 - 2² = 1720339669 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 1720339673.

It is not an unprimeable number, because it can be changed into a prime (1720339603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66166898 + ... + 66166923.

It is an arithmetic number, because the mean of its divisors is an integer number (463168377).

Almost surely, 2^1720339673 is an apocalyptic number.

1720339673 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1720339673 is a deficient number, since it is larger than the sum of its proper divisors (132333835).

1720339673 is a wasteful number, since it uses less digits than its factorization.

1720339673 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132333834.

The product of its (nonzero) digits is 142884, while the sum is 41.

The square root of 1720339673 is about 41476.9776261482. The cubic root of 1720339673 is about 1198.2241494160.

The spelling of 1720339673 in words is "one billion, seven hundred twenty million, three hundred thirty-nine thousand, six hundred seventy-three".