43279921 has 2 divisors, whose sum is σ = 43279922. Its totient is φ = 43279920.

The previous prime is 43279897. The next prime is 43279993. The reversal of 43279921 is 12997234.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29322225 + 13957696 = 5415^2 + 3736^2 .

It is a cyclic number.

It is not a de Polignac number, because 43279921 - 2⁵ = 43279889 is a prime.

It is not a weakly prime, because it can be changed into another prime (43279421) 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, 21639960 + 21639961.

It is an arithmetic number, because the mean of its divisors is an integer number (21639961).

Almost surely, 2^43279921 is an apocalyptic number.

It is an amenable number.

43279921 is a deficient number, since it is larger than the sum of its proper divisors (1).

43279921 is an equidigital number, since it uses as much as digits as its factorization.

43279921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27216, while the sum is 37.

The square root of 43279921 is about 6578.7476771799. The cubic root of 43279921 is about 351.0983753066.

The spelling of 43279921 in words is "forty-three million, two hundred seventy-nine thousand, nine hundred twenty-one".