4128861321 has 12 divisors (see below), whose sum is σ = 6422673348. Its totient is φ = 2540837664.

The previous prime is 4128861299. The next prime is 4128861377. The reversal of 4128861321 is 1231688214.

4128861321 is a `hidden beast` number, since 4 + 12 + 8 + 8 + 613 + 21 = 666.

4128861321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 167417721 + 3961443600 = 12939^2 + 62940^2 .

It is not a de Polignac number, because 4128861321 - 2¹⁹ = 4128337033 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (4128861221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17644590 + ... + 17644823.

It is an arithmetic number, because the mean of its divisors is an integer number (535222779).

Almost surely, 2^4128861321 is an apocalyptic number.

It is an amenable number.

4128861321 is a deficient number, since it is larger than the sum of its proper divisors (2293812027).

4128861321 is a wasteful number, since it uses less digits than its factorization.

4128861321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35289432 (or 35289429 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 4128861321 is about 64256.2162051268. The cubic root of 4128861321 is about 1604.2674258922.

The spelling of 4128861321 in words is "four billion, one hundred twenty-eight million, eight hundred sixty-one thousand, three hundred twenty-one".