728102005 has 4 divisors (see below), whose sum is σ = 873722412. Its totient is φ = 582481600.

The previous prime is 728101973. The next prime is 728102009. The reversal of 728102005 is 500201827.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 500201827 = 11353 ⋅44059.

It can be written as a sum of positive squares in 2 ways, for example, as 155600676 + 572501329 = 12474^2 + 23927^2 .

It is not a de Polignac number, because 728102005 - 2⁵ = 728101973 is a prime.

It is a super-3 number, since 3×728102005³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728102009) 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, 72810196 + ... + 72810205.

It is an arithmetic number, because the mean of its divisors is an integer number (218430603).

Almost surely, 2^728102005 is an apocalyptic number.

It is an amenable number.

728102005 is a deficient number, since it is larger than the sum of its proper divisors (145620407).

728102005 is a wasteful number, since it uses less digits than its factorization.

728102005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145620406.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 728102005 is about 26983.3653386675. The cubic root of 728102005 is about 899.6303028911.

The spelling of 728102005 in words is "seven hundred twenty-eight million, one hundred two thousand, five".