12721163828 has 6 divisors (see below), whose sum is σ = 22262036706. Its totient is φ = 6360581912.

The previous prime is 12721163821. The next prime is 12721163831. The reversal of 12721163828 is 82836112721.

It can be written as a sum of positive squares in only one way, i.e., 12715268644 + 5895184 = 112762^2 + 2428^2 .

It is a super-2 number, since 2×12721163828² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12721163821) 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 as a sum of consecutive naturals, namely, 1590145475 + ... + 1590145482.

It is an arithmetic number, because the mean of its divisors is an integer number (3710339451).

Almost surely, 2^12721163828 is an apocalyptic number.

It is an amenable number.

12721163828 is a deficient number, since it is larger than the sum of its proper divisors (9540872878).

12721163828 is a wasteful number, since it uses less digits than its factorization.

12721163828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3180290961 (or 3180290959 counting only the distinct ones).

The product of its digits is 64512, while the sum is 41.

The spelling of 12721163828 in words is "twelve billion, seven hundred twenty-one million, one hundred sixty-three thousand, eight hundred twenty-eight".