12820728266 has 8 divisors (see below), whose sum is σ = 19231603524. Its totient is φ = 6410193760.

The previous prime is 12820728229. The next prime is 12820728281. The reversal of 12820728266 is 66282702821.

It can be written as a sum of positive squares in 2 ways, for example, as 12730383241 + 90345025 = 112829^2 + 9505^2 .

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

It is a super-2 number, since 2×12820728266² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55046 + ... + 169326.

Almost surely, 2^12820728266 is an apocalyptic number.

12820728266 is a deficient number, since it is larger than the sum of its proper divisors (6410875258).

12820728266 is a wasteful number, since it uses less digits than its factorization.

12820728266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170376.

The product of its (nonzero) digits is 258048, while the sum is 44.

The spelling of 12820728266 in words is "twelve billion, eight hundred twenty million, seven hundred twenty-eight thousand, two hundred sixty-six".