43940921 has 2 divisors, whose sum is σ = 43940922. Its totient is φ = 43940920.

The previous prime is 43940893. The next prime is 43940927. The reversal of 43940921 is 12904934.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29041321 + 14899600 = 5389^2 + 3860^2 .

It is a cyclic number.

It is not a de Polignac number, because 43940921 - 2¹⁰ = 43939897 is a prime.

It is not a weakly prime, because it can be changed into another prime (43940927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21970460 + 21970461.

It is an arithmetic number, because the mean of its divisors is an integer number (21970461).

Almost surely, 2^43940921 is an apocalyptic number.

It is an amenable number.

43940921 is a deficient number, since it is larger than the sum of its proper divisors (1).

43940921 is an equidigital number, since it uses as much as digits as its factorization.

43940921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 43940921 is about 6628.7948376760. The cubic root of 43940921 is about 352.8767556023.

The spelling of 43940921 in words is "forty-three million, nine hundred forty thousand, nine hundred twenty-one".