1721441723 has 4 divisors (see below), whose sum is σ = 1724232360. Its totient is φ = 1718651088.

The previous prime is 1721441719. The next prime is 1721441737. The reversal of 1721441723 is 3271441271.

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

It is a cyclic number.

It is not a de Polignac number, because 1721441723 - 2² = 1721441719 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 1721441723.

It is not an unprimeable number, because it can be changed into a prime (1721441713) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1394393 + ... + 1395626.

It is an arithmetic number, because the mean of its divisors is an integer number (431058090).

Almost surely, 2^1721441723 is an apocalyptic number.

1721441723 is a deficient number, since it is larger than the sum of its proper divisors (2790637).

1721441723 is an equidigital number, since it uses as much as digits as its factorization.

1721441723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2790636.

The product of its digits is 9408, while the sum is 32.

The square root of 1721441723 is about 41490.2605800446. The cubic root of 1721441723 is about 1198.4799556915.

Adding to 1721441723 its reverse (3271441271), we get a palindrome (4992882994).

The spelling of 1721441723 in words is "one billion, seven hundred twenty-one million, four hundred forty-one thousand, seven hundred twenty-three".