2728443721 has 8 divisors (see below), whose sum is σ = 2739055104. Its totient is φ = 2717853600.

The previous prime is 2728443709. The next prime is 2728443733. The reversal of 2728443721 is 1273448272.

It is an interprime number because it is at equal distance from previous prime (2728443709) and next prime (2728443733).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2728443721 - 2⁵ = 2728443689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2728443761) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 280896 + ... + 290446.

It is an arithmetic number, because the mean of its divisors is an integer number (342381888).

Almost surely, 2^2728443721 is an apocalyptic number.

It is an amenable number.

2728443721 is a deficient number, since it is larger than the sum of its proper divisors (10611383).

2728443721 is an equidigital number, since it uses as much as digits as its factorization.

2728443721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10631.

The product of its digits is 150528, while the sum is 40.

The square root of 2728443721 is about 52234.5069948975. The cubic root of 2728443721 is about 1397.3493589885.

The spelling of 2728443721 in words is "two billion, seven hundred twenty-eight million, four hundred forty-three thousand, seven hundred twenty-one".