40209866 has 4 divisors (see below), whose sum is σ = 60314802. Its totient is φ = 20104932.

The previous prime is 40209853. The next prime is 40209887. The reversal of 40209866 is 66890204.

40209866 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.

It can be written as a sum of positive squares in only one way, i.e., 31595641 + 8614225 = 5621^2 + 2935^2 .

It is a Curzon number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 10052465 + ... + 10052468.

Almost surely, 2^40209866 is an apocalyptic number.

40209866 is a deficient number, since it is larger than the sum of its proper divisors (20104936).

40209866 is a wasteful number, since it uses less digits than its factorization.

40209866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20104935.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 40209866 is about 6341.1249790554. The cubic root of 40209866 is about 342.5922560363.

The spelling of 40209866 in words is "forty million, two hundred nine thousand, eight hundred sixty-six".