43720129 has 4 divisors (see below), whose sum is σ = 43744000. Its totient is φ = 43696260.

The previous prime is 43720123. The next prime is 43720133. The reversal of 43720129 is 92102734.

43720129 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43720129 is a prime.

It is a super-2 number, since 2×43720129² = 3822899359553282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43720097 and 43720106.

It is not an unprimeable number, because it can be changed into a prime (43720123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8937 + ... + 12934.

It is an arithmetic number, because the mean of its divisors is an integer number (10936000).

Almost surely, 2^43720129 is an apocalyptic number.

It is an amenable number.

43720129 is a deficient number, since it is larger than the sum of its proper divisors (23871).

43720129 is a wasteful number, since it uses less digits than its factorization.

43720129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23870.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 43720129 is about 6612.1198567479. The cubic root of 43720129 is about 352.2847241125.

The spelling of 43720129 in words is "forty-three million, seven hundred twenty thousand, one hundred twenty-nine".