43021729 has 2 divisors, whose sum is σ = 43021730. Its totient is φ = 43021728.

The previous prime is 43021717. The next prime is 43021733. The reversal of 43021729 is 92712034.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42928704 + 93025 = 6552^2 + 305^2 .

It is a cyclic number.

It is not a de Polignac number, because 43021729 - 2¹⁵ = 42988961 is a prime.

It is a super-2 number, since 2×43021729² = 3701738332298882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 43021697 and 43021706.

It is not a weakly prime, because it can be changed into another prime (43021739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21510864 + 21510865.

It is an arithmetic number, because the mean of its divisors is an integer number (21510865).

Almost surely, 2^43021729 is an apocalyptic number.

It is an amenable number.

43021729 is a deficient number, since it is larger than the sum of its proper divisors (1).

43021729 is an equidigital number, since it uses as much as digits as its factorization.

43021729 is an odious number, because the sum of its binary digits is odd.

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

The square root of 43021729 is about 6559.0951357638. The cubic root of 43021729 is about 350.3988079901.

The spelling of 43021729 in words is "forty-three million, twenty-one thousand, seven hundred twenty-nine".