801728689 has 4 divisors (see below), whose sum is σ = 801823860. Its totient is φ = 801633520.

The previous prime is 801728677. The next prime is 801728701. The reversal of 801728689 is 986827108.

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

It is an interprime number because it is at equal distance from previous prime (801728677) and next prime (801728701).

It can be written as a sum of positive squares in 2 ways, for example, as 104346225 + 697382464 = 10215^2 + 26408^2 .

It is a cyclic number.

It is not a de Polignac number, because 801728689 - 2⁵ = 801728657 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (801728489) 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, 33574 + ... + 52255.

It is an arithmetic number, because the mean of its divisors is an integer number (200455965).

Almost surely, 2^801728689 is an apocalyptic number.

It is an amenable number.

801728689 is a deficient number, since it is larger than the sum of its proper divisors (95171).

801728689 is an equidigital number, since it uses as much as digits as its factorization.

801728689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95170.

The product of its (nonzero) digits is 387072, while the sum is 49.

The square root of 801728689 is about 28314.8139495918. The cubic root of 801728689 is about 928.9859409727.

The spelling of 801728689 in words is "eight hundred one million, seven hundred twenty-eight thousand, six hundred eighty-nine".