43838728129 has 15 divisors (see below), whose sum is σ = 51154111203. Its totient is φ = 37567258848.

The previous prime is 43838728127. The next prime is 43838728183. The reversal of 43838728129 is 92182783834.

It is a happy number.

The square root of 43838728129 is 209377.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11886450625 + 31952277504 = 109025^2 + 178752^2 .

It is not a de Polignac number, because 43838728129 - 2¹ = 43838728127 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 43838728129.

It is not an unprimeable number, because it can be changed into a prime (43838728127) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 10257337 + ... + 10261609.

Almost surely, 2^43838728129 is an apocalyptic number.

43838728129 is a gapful number since it is divisible by the number (49) formed by its first and last digit.

43838728129 is the 209377-th square number.

43838728129 is the 104689-th centered octagonal number.

It is an amenable number.

43838728129 is a deficient number, since it is larger than the sum of its proper divisors (7315383074).

43838728129 is an frugal number, since it uses more digits than its factorization.

43838728129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8574 (or 4280 counting only the distinct ones).

The product of its digits is 4644864, while the sum is 55.

The spelling of 43838728129 in words is "forty-three billion, eight hundred thirty-eight million, seven hundred twenty-eight thousand, one hundred twenty-nine".