40943821 has 2 divisors, whose sum is σ = 40943822. Its totient is φ = 40943820.

The previous prime is 40943813. The next prime is 40943831. The reversal of 40943821 is 12834904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29041321 + 11902500 = 5389^2 + 3450^2 .

It is a cyclic number.

It is not a de Polignac number, because 40943821 - 2³ = 40943813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40943831) 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, 20471910 + 20471911.

It is an arithmetic number, because the mean of its divisors is an integer number (20471911).

Almost surely, 2^40943821 is an apocalyptic number.

It is an amenable number.

40943821 is a deficient number, since it is larger than the sum of its proper divisors (1).

40943821 is an equidigital number, since it uses as much as digits as its factorization.

40943821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 40943821 is about 6398.7358907834. The cubic root of 40943821 is about 344.6641582316.

The spelling of 40943821 in words is "forty million, nine hundred forty-three thousand, eight hundred twenty-one".